THE  BRIDGEWATER  TREATISES 

ON  THE  POWER,  WISDOM,  AND  GOODNESS  OF  GOD 
AS  MANIFESTED  IN  THE  CREATION. 


TREATISE  IV. 

THE  HAND,  ITS  MECHANISM  AND  VITAL  ENDOWMENTS, 
AS  EVINCING  DESIGN. 


BY  SIR  CHARLES  BELL,  K.  G.  H.  F.  R.  S.  L.  & E. 


Digitized  by  the  Internet  Archive 
in  2016 


https://archive.org/details/handitsmechanism01bell 


THE  HAND, 

ITS  MECHANISM  AND  VITAL  ENDOWMENTS, 


AS  EVINCING  DESIGN. 


GEOKGIA  MEBICL  u 


9CIETI 


SIR  CHARLES  BELL,  K.  G.  H. 
F.R.S.  L.&E. 


PHILADELPHIA: 

CAREY,  LEA  & BLATs'CHARD. 


1833. 


NOTICE. 


The  series  of  Treatises,  of  which  the  present  is  one,  is  published, 
under  the  following  circumstances  : 

The  Right  Honourable  and  Reverend  Francis  Henry,  Earl 
of  Bridgewater,  died  in  the  month  of  February,  1829  ; and  by  his 
last  Will  and  Testament,  bearing  date  the  25th  of  February,  1825, 
he  directed  certain  T rustees  therein  named  to  invest  in  the  public  funds 
the  sum  of  Eight  thousand  pounds  sterling  : this  sum,  with  the  ac- 
cruing dividends  thereon,  to  be  held  at  the  disposal  of  the  President, 
for  the  time  being,  of  the  Royal  Society  of  London,  to  be  paid  to  the 
person  or  persons  nominated  by  him.  The  Testator  further  directed, 
that  the  person  or  persons  selected  by  the  said  President  should  be 
appointed  to  write,  print,  and  publish  one  tliousand  copies  of  a work 
On  the  Power,  Wisdom,  and  Goodness  of  God,  as  manifested  in  the 
Creation ; illustrating  such  work  by  all  reasonable  arguments,  as  for  in- 
stance the  variety  and  formation  of  God’s  creatures  in  the  animal,  vege- 
table, and  mineral  kingdoms  ; the  effect  of  digestion,  and  thereby  of  con- 
version ; the  construction  of  the  hand  of  man,  and  an  infinite  variety  of 
other  arguments ; as  also  by  discoveries  ancient  and  modern,  in  arts, 
sciences,  and  the  lohole  extent  of  literature.  He  desired,  moreover, 
that  the  profits  arising  from  the  sale  of  the  works  so  published  should 
be  paid  to  the  authors  of  the  works. 

The  late  President  of  the  Royal  Society,  Davies  Gilbert,  Esq. 
requested  the  assistance  of  his  Grace  the  Archbishop  of  Canterbury 
and  of  the  Bishop  of  London,  in  determining  upon  the  best  mode  of 
carrying  into  effect  the  intentions  of  the  T estator.  Acting  with  their 
advice,  and  with  the  concurrence  of  a nobleman  immediately  con- 
nected with  the  deceased,  Mr.  Davies  Gilbert  appointed  the  follow- 
ing eight  gentlemen  to  write  separate  Treatises  on  the  different 
branches  of  the  subject  as  here  stated  : 

THE  REV.  THOMAS  CHALMERS,  D.  D. 

professor  of  divinity  in  the  university  of  EDINBURGH. 

ON  THE  ADAPTATION  OF  EXTERNAL  NATURE  TO  THE  MORAL 
AND  INTELLECTUAL  CONSTITUTION  OF  MAN. 


JOHN  KIDD,  M.  D.  F.  R.  S. 

REGIUS  professor  OF  MEDICINE  IN  THE  UNIVERSITY  OF  OXFORD. 

ON  THE  ADAPTATION  OF  EXTERNAL  NATURE  TO  THE 
PHYSICAL  CONDITION  OF  MAN. 


VI 


NOTICE. 


THE  REV.  WILLIAM  "WHEWELL,  3\I.  A.  F R.  S. 

FELLOW  OF  TBINITF  COLLEGE,  CAMBRIDGE. 

ON  ASTRONOMY  AND  GENERAL  PHYSICS. 


SIR  CHARLES  BELL,  K.  H.  F.  R.  S. 

THE  HAND  : ITS  MECHANISM  AND  VITAL  ENDOWMENTS 
AS  EVINCING  DESIGN. 


PETER  MARK  ROGET,  M.  D. 

FELLOW  OF  AND  SECRETARY  TO  THE  ROYAL  SOCIETY. 

ON  ANIMAL  AND  VEGETABLE  PHYSIOLOGY. 


THE  REV.  WILLIAM  BUCKLAND,  D.  D.  F.  R.  S. 

CANON  OF  CHRIST  CHURCH,  AND  PROFESSOR  OP  GEOLOGY  IN  THE 
UNIVERSITY  OP  OXFORD. 

ON  GEOLOGY  AND  MINERALOGY. 


THE  REV.  WILLIAM  KIRBY,  M.  A.  F.  R.  S. 

ON  THE  HISTORY,  HABITS,  AND  INSTINCTS  OF  ANIMALS. 


WILLIAM  PROUT,  M.  D.  F.  R.  S. 

ON  CHEMISTRY,  METEOROLOGY,  AND  THE  FUNCTION 
OF  DIGESTION. 


His  Royal  Highness  the  Duke  of  Sussex,  President  of  the 
Royal  Society,  having  desired  that  no  unnecessary  delay  should  take 
place  in  the  publication  of  the  above  mentioned  treatises,  they  will 
appear  at  short  intervals,  as  they  are  ready  for  publication. 


PREFACE. 


When  one  has  to  maintain  an  argument,  he  will 
be  listened  to  more  willingly  if  he  is  known  to  be  un- 
biassed, and  to  express  his  natural  sentiments.  The 
reflexions  contained  in  these  pages  have  not  been  sug- 
gested by  the  occasion  of  the  Bridgewater  Treatises, 
but  arose,  long  ago,  in  a course  of  study,  directed  to 
other  objects.  An  anatomical  teacher,  who  is  him- 
self aware  of  the  higher  bearings  of  his  science,  can 
hardly  neglect  the  opportunity  which  the  demonstra- 
tions before  him  afford,  of  making  an  impression  upon 
the  minds  of  those  young  men  who,  for  the  most 
part,  receive  the  elements  of  their  professional  educa- 
tion from  him  ; and  he  is  naturally  led  to  indulge  in 
such  trains  of  reflexion,  as  will  be  found  in  this  essa}'. 

So  far  back  as  the  year  1813,  the  late  excellent 
vicar  of  Kensington,  Mr.  Rennell,  attended  the  au- 
thor’s lectures,  and  found  him  engaged  in  maintain- 
ing the  principles  of  the  English  school  of  Ph5rsiolog}-, 
and  in  exposing  the  futility  of  the  opinions  of  those 
French  philosophers  and  physiologists,  who  represented 
life  as  the  mere  physical  result  of  certain  combinations 
and  actions  of  parts,  by  them  termed  Organization. 

That  gentleman  thought  that  the  subject  admitted 
of  an  argument  which  it  became  him  to  use,  in  his 
office  of  “ Christian  Advocate.”*  This  will  show  the 


An  office  in  the  University  of  Cambridge. 


Vlll 


PREFACE. 


reader  that  the  sentiments  and  the  views,  which  a 
sense  of  duty  to  the  young  men  about  him  induced 
the  author  to  deliver,  and  which  Mr.  Rennell  heard 
only  by  accident,  arose  naturally  out  of  those  studies. 

It  was  at  the  desire  of  the  Lord  Chancellor  that  the 
author  wrote  the  essay  on  “ Annual  Mechanics and 
it  Avas  probably  from  a belief  that  the  author  felt 
the  importance  of  the  subjects  touched  upon  in  that 
essay,  that  his  lordship  Avas  led  to  do  him  the  fur- 
ther honour  of  asking  him  to  join  with  him  in  illustra- 
ting the  “ Natural  Theology”  of  Dr.  Paley. 

That  request  was  especially  important,  as  showing, 
that  the  conclusions,  to  which  the  author  had  arriv- 
ed, Avere  not  the  peculiar  or  accidental  suggestions  of 
professional  feeling,  nor  of  solitary  study,  which  is  so 
apt  to  lead  to  enthusiasm,  but  that  the  powerful  and 
masculine  mind  of  Lord  Brougham  was  directed  to 
the  same  object : that  he,  Avho  in  early  life  was  dis- 
tinguished for  his  successful  prosecution  of  science, 
and  Avho  has  never  forgotten  her  interests  amidst 
the  most  arduous  and  actiA^e  duties  of  his  high  station, 
encouraged  and  partook  of  these  sentiments. 

Thus,  from  at  first  maintaining  that  design  and 
benevolence  Avere  every  Avhere  visible  in  the  natural 
Avorld,  circumstances  haA'e  gradually  draAvn  the  au- 
thor to  support  these  opinions  more  ostentatiousl}’  and 
elaborately  than  was  his  original  Avish. 

The  author  cannot  conceal  from  himself  the  disad- 
vantages to  Avhich  he  is  exposed  in  coming  before  the 
public,  not  only  with  a Avork,  in  some  measure  extra- 
professional, but  AA'ith  associates,  distinguished  by 


PREFACE. 


IX 


classical  elegance  of  style,  as  well  as  by  science.  He 
must  entreat  the  reader  to  remember  that  he  was,  ear- 
ly and  long,  devoted  to  the  study  of  anatomy ; and 
with  a feeling  (right  or  wrong)  that  it  surpassed  all 
other  studies,  in  interest  and  usefulness.  This  made 
him  negligent  of  those  acquirements  which  would 
have  better  fitted  him  for  the  honourable  association 
in  which  he  has  been  placed  : and  no  one  can  feel 
more  deeply  that  the  suggestions  which  occur  in  the 
intervals  of  an  active  professional  life,  must  always  be 
unfavourably  contrasted  with  what  comes  of  the 
learned  leisure  of  a College. 

The  author  has  to  acknowledge  his  obligation  to 
Davies  Gilbert,  Esq.  late  President  of  the  Royal  Socie- 
ty, for  having  assigned  to  him  a task  of  so  much  inter- 
est. When  he  undertook  it,  he  thought  only  of  the 
pleasure  of  pursuing  these  investigations,  and  perhaps 
too  little  of  what  the  public  were  entitled  to  expect 
from  an  Essay  composed  in  circumstances  so  peculiar, 
and  forming  a part  in  “ this  great  argument.” 


CONTENTS. 


Page 

Chap.  I.  Introductory  .....  15 

Chap.  II.  Definition  of  the  Hand  . . .26 

Its  Mechanism  . . . . .27 

Conformity  of  the  Skeleton  to  the  Extremity  . . ib. 

Bones  of  the  Extremity  not  adapted  to  Man  alone  . 28 

Fossil  Bones  exhibit  the  Extent  of  the  System  . . 30 

Animals  the  most  uncouth,  in  every  Respect  adapted  to 
their  Condition  .....  32 

Mistaken  Compassion  for  Animals  . . .34 

Animals  suited  to  the  progressive  Changes  of  the  Earth 
and  Elements  ...  . . .33 

Succession  and  Grouping  of  Animals  . . .39 

Chap.  III.  The  Comparative  Anatomy  of  the  Hand  . 42 

Comparative  View  of  the  Anatomy  of  the  SAowlder  . 43 

The  Arms  wanting  in  a Boy  . . . .49 

The  Structure  of  the  Horse’s  Shoulder  . . .51 

In  the  Chelonian  Order  . . . .54 

The  Humerus.  Spirit  in  which  the  Demonstration  should 

be  given  ......  59 

Peculiarities  in  the  Mole  . . . .60 

Bat  ......  .61 

Ant-Eater  ....  . . 62 

Adaptation  of  the  Anatomy  in  Birds  . . .64 

The  .inatomy  of  the  Fore  Arm  . . . .69 

The  Action  of  the  Splint  Bone  in  the  Horse  . . 72 

Horse’s  Foot  . .....  74 


XU 


CONTENTS. 


P»ge 

Of  Ruminants  ......  76 

Contrast  in  the  Bone  of  the  Elephant  and  the  Camel  . 77 

Mechanism  in  the  Lion’s  Claw  . . . . 79 

Megalonis  . . . . . . ib. 

Criticism  by  Cuvier  . . . . .80 

The  Foot  of  the  Gluadrumana  . . . .81 

Of  Amphibia  .....  83 

Plesiosaurus  and  Ichthyosaurus  . . .85 

Peculiarities  and  Provisions  of  the  Human  Hand  . 86 

Chap.  IV.  Of  the  Muscles  of  the  Arm  and  Hand  89 
Action  of  the  Muscles  of  the  Arm  . . . ib. 

Interchange  of  Velocity  for  Force,  exemplified  in  the 
Muscles  of  the  Arm  . . . . .93 

Illustrated  by  the  Lever  and  Fly-wheel  . . .94 

Aluscles  of  the  Lion’s  Extremity  . . .96 

Vital  property  of  the  Muscles  ....  ib. 
Peculiarities  in  the  Circulation  of  the  Extremities  as  sub- 
servient to  muscular  Action  . . . .97 

Of  the  Right  and  Left  Hands  . . . .98 

Chap.  V.  The  Substitution  of  other  Organs  for 

THE  Hand  ......  100 

Chap.  VI.  The  Argument  pursued,  from  the  Compa- 
rative Anatomy  .....  105 

Chap.  VII.  Of  Sensibility  and  Touch  . . 116 

The  Sensibility  of  the  Surface  compared  with  that  of 

the  deeper  Parts  . . . . .113 

Pain  the  Safeguard  of  the  Body  . . . 121 

The  protecting  Sensibility  of  the  Eye  compared  with  the 

Sensibility  of  the  Heart  ....  124 

Pleasurable  Sensations  could  not  have  been  tlie  Motives 

to  Action  ......  123 

Chap.  VIII.  Of  the  Senses  generally,  introductory 

TO  the  Sense  OF  Touch  ....  131 

The  Sense  of  Touch  .....  136 

Of  the  Cuticle  . . ....  138 


CONTENTS.  Xiif 

' Page 

The  Hoofs  of  Animals  and  their  Sensibility  . . 140 

Chap.  IX.  Op  the  Muscular  Sense  . . . 145 

Of  the  Sensibility  of  the  Infant  to  Impressions,  and  gra- 
dual Improvement  of  the  Sense  of  Touch  . . 146 

Of  the  same  in  Insects  and  Fishes  . . .152 

Loss  of  the  Sense  . . . . .153 

Pleasures  arising  from  the  Muscular  Sense  . .154 


Chap.  X.  The  Hand  not  the  Source  op  Ingenuitt 
OR  Contrivance,  nor  consequently  op  Man’s 
superiority  . . . . .157 

The  Subject  illustrated  by  the  Organs  of  Speech  . 161 

The  Ingenuity  of  the  Hand  has  made  a Revolution  in 
the  Arts  .....  . 162 

Changes  in  the  Globe  and  successive  Epochs  . . 164 

Conclusion  ...  . . . . 168 


ADDITIONAL  ILLUSTRATIONS. 

The  Mechanical  properties  op  the  solid  Structure  of 


the  Animal  Body  considered  . . . 171 

Substitute  for  the  Skeleton  in  the  lower  Animals  . 172 

Mechanical  Properties  in  Bone,  or  in  the  true  Skeleton  175 
The  Muscular  and  Elastic  Forces  . . . 181 

Comparison  of  the  Eye  with  the  Hand  . . 183 

The  Motion  of  the  Eye  considered  in  regard  to  the  Ef- 
fect of  Light  and  Shade  in  a Picture  . . 197 

Addition  to  the  concluding  Chapter  . . 204 

APPENDIX. 

E.xplanation  of  Terms  .....  209 


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THE  HAND, 

ITS  MECHANISM  AND  VITAL  ENDOW- 
MENTS, AS  EVINCING  DESIGN. 


CHAPTER  I. 

If  we  contemplate  any  natural  object,  especially 
any  part  of  animated  nature,  fully  and  in  all  its  bear- 
ings, we  can  arrive  only  at  this  conclusion  : that  there 
is  design  in  the  mechanical  construction,  benevolence 
shown  in  the  living  properties,  and  that  good  predo- 
minates : we  shall  perceive  that  the  sensibilities  of 
the  body  have  a relation  to  the  qualities  of  things 
external,  and  that  delicacy  of  texture  is  a necessary 
consequence  of  this  relation. 

Wonderful,  and  exquisitely  constructed,  as  the  me- 
chanical appliances  are  for  the  protection  of  this  deli- 
cate structure,  tlrey  are  altogether  insufficient ; and 
a protection  of  a very  different  kind,  which  shall  ani- 
mate the  body  to  the  utmost  exertion,  is  requisite  for 
safety.  Pain,  whilst  it  is  a necessary  contrast  to  its 
opposite  pleasure,  is  the  great  safeguard  of  the  frame. 
Finally,  as  to  man,  we  shall  be  led  to  infer  that  the 
pains  and  pleasures  of  mere  bodily  sense  (with  yet 
more  benevolent  intention)  carry  us  onward,  through 
the  developementand  improvement  of  the  mind  itself^ 
to  higher  aspirations. 


16 


INTRODUCTORY  CHAPTER. 


Such  is  the  course  of  reasoning  which  I propose  to 
follow  in  giving  an  account  of  the  hand  and  arm,  con- 
trasting them  with  the  corresponding  parts  of  ^i^’ing 
creatures,  through  all  the  divisions  of  the  chain  of 
vertebrated  animals. 

When  I first  thought  of  extending  my  notes  on  this 
subject,  it  appeared  to  me  that  I might  have  many 
other  topics  more  prolific  in  proofs  of  design,  and  more 
interesting ; but  I now  find  that  there  is  no  end  to 
illustration,  and  that  the  subject  branches  out  inter- 
minably. 

Some  may  conceive  that  as  I have  for  my  title  the 
Human  Hand,  and  the  relation  of  the  solid  structures 
of  the  animal  frame,  it  will  lead  me  to  consider  the 
body  as  a machine  only.  I neither  see  the  necessity 
for  this,  nor  do  I acknowledge  the  danger  of  consider- 
ing it  in  that  light.  I embark  fearlessly  in  the  inves- 
tigation, convinced  that,  yielding  to  the  current  of 
thought,  and  giving  the  fullest  scope  to  enquhy,  there 
can  be  no  hidden  danger  if  the  mind  be  free  from 
vicious  bias.  I cannot  see  how  scepticism  should  arise 
out  of  the  contemplation  of  the  structure  and  me- 
chanism of  the  animal  body. 

Let  us  for  a moment  think  what  is  the  natural  re- 
sult of  examining  the  hmnan  body  as  a piece  of  ma- 
chineiy,  and  let  us  see  whether  it  makes  the  creation 
of  man  more  or  less  important  in  his  relation  to  the 
whole  scheme  of  nature. 

Suppose  that  there  is  placed  before  us  a machine 
for  raising  great  weights,  be  it  the  simplest  of  all,  the 
wheel  and  axle.  We  are  given  to  understand  that 
this  piece  of  mechanism  has  the  property  of  multiply- 
ing the  power  of  the  hand.  But  a youth  of  subtile 
mind  may  say,  I do  not  believe  that  it  is  possible  so  to 
multiply  the  power  of  the  hand  ; and  if  the  mechani- 
cian be  a philosopher,  he  will  rather  applaud  the  spirit 
of  doubt.  If  he  condescend  to  explain,  he  will  say, 
that  the  piles  driven  into  the  ground,  or  the  screws 
which  unite  the  machinery  to  the  beams,  are  the  fixed 


INTRODUCTORY  CHAPTER. 


17 


points  which  resist  in  the  working  of  the  machine ; 
that  their  resistance  is  a necessary  condition,  since  it 
is  thrown,  together  with  the  power  of  the  hand,  on  the 
weight  to  be  raised.  And  he  will  add  that  the  mul- 
tiplication of  wheels  does  not  alter  the  principle  of 
action,  which  every  one  may  see  in  the  simple  lever,  to 
result  from  the  resistance  of  the  fulcrum  or  point,  on 
which  it  rests. 

Now  grant  that  man’s  body  is  a machine,  where 
are  the  points  of  resistance  ? are  they  not  in  the 
ground  he  stands  upon  1 This  leads  us  to  enquire  by 
what  property  we  stand.  Is  it  by  the  weight  of  the 
body,  or  in  other  words,  is  it  by  the  attraction  of  the 
earth  1 The  terms  attraction,  or  gravitation,  lead  at 
once  to  the  philosophy  of  the  question.  We  stand 
because  the  body  has  weight,  and  a resistance,  in  pro- 
portion to  the  matter  of  the  animal  frame,  and  the 
magnitude  of  the  globe  itself.  We  Avait  not  at  pre- 
sent to  observe  the  adjustment  of  the  strength  of  the 
frame,  the  resistance  of  the  bones,  the  elasticity  of  the 
joints,  and  the  power  of  the  muscles  to  the  weight  of 
the  whole.  Our  attention  is  directed  to  the  relations 
which  the  frame  has  to  the  earth  Ave  are  placed  upon. 

Some  philosoplrers,  Avho  have  considered  the  mat- 
ter curiously,  have  said,  that  if  man  Avere  translated 
bodily  to  another  planet,  and  Avere  it  smaller  than  the 
earth,  he  Avould  be  too  light,  and  he  Avould  Avalk  like 
one  Avading  in  deep  Avater.  If  the  planet  Avere  larger, 
the  attraction  of  his  body  AA’ould  make  him  feel  as  if 
his  limbs  Avere  loaded  Avith  lead  ; nay,  the  attraction 
might  be  so  great  as  to  destroy  the  fabric  of  the  body,  , 
crushing  bones  and  all.* 

HoAvever  idle  these  fancies  may  be,  there  is  no 
doubt  that  the  animal  frame  is  formed  Avith  a due 
relation  to  the  earth  Ave  inhabit,  and  that  the  parts  of 
the  animal  body,  and  aa'c  may  say  the  strength  of  the 

* The  matter  of  Jupiter  is  as  330,600  to  1000  of  our  Earth.  The 
diameter  of  Pallas  is  80  miles;  the  Earth  is  7,911  miles  in  diameter. 

2* 


18 


INTRODUCTORY  CHAPTER. 


materials,  have  as  certainly  a correspondence  with  the 
weight,  as  the  wheels  and  levers  of  a machine,  or  the 
scatfolding  which  sustains  them,  have  relation  to  the 
force  and  velocity  of  the  machinery,  or  the  load  that 
they  are  employed  to  raise. 

The  mechanism  and  organization  of  animals  have 
been  often  brought  forward  for  a different  purpose 
from  that  for  which  I use  them.  We  find  it  said,  that 
it  is  incomprehensible  that  an  all-powerful  Being 
should  manifest  his  will  in  this  manner ; that  mecha- 
nical contrivance  implies  difficulties  overcome  : and 
how  strange  it  is,  they  add,  that  the  perceptions  of  the 
mind,  which  might  have  been  produced  by  some  di- 
rect means,  or  have  arisen  spontaneously,  are  received 
through  an  instrument  so  fine  and  complex  as  the 
eye  ; — and  which  requires  the  creation  of  the  element 
of  light,  to  enter  the  organ  and  to  cause  vision. 

For  my  own  part,  I think  it  most  natiual  to  con- 
template the  subject  quite  differently.  We  perhaps 
presume  too  much,  when  we  sa)',  that  light  has  been 
created  for  the  purpose  of  vision.  We  are  hardly  en- 
titled to  pass  over  its  properties  as  a chemical  agent, 
its  influence  on  the  gases,  and,  in  all  probability  on  the 
atmosphere,  its  importance  to  vegetation,  to  the  form- 
ation of  the  aromatic  and  volatile  principles,  and  to 
fructification,  its  influence  on  the  animal  surface  by 
invigorating  the  circidation,  and  imparting  health. 
In  relation  to  our  present  subject,  it  seems  more  ra- 
tional to  consider  light  as  second  only  to  attraction, 
in  respect  to  its  importance  in  nature,  and  as  a link 
connecting  systems  of  infinite  remoteness. 

To  have  a conception  of  this  we  must  tutor  our 
minds,  and  acquire  some  measme  of  the  velocity  of 
light,  and  of  the  space  which  it  fills.  It  is  not  suffi- 
cient to  say  that  it  moves  200,000  miles  in  a second  ; 
for  we  can  comprehend  no  such  degree  of  velocity. 
If  we  are  further  informed  that  the  earth  is  distant 
from  the  sun  95,000,000  of  miles,  and  that  light  tra- 
verses the  space  in  8 minutes  and  l-8th,  it  is  but 


I^■TRODUCTORT  CHAPTER. 


19 


another  way  of  affirming  the  inconceivable  rapidity 
of  its  transmission.  Astronomers,  the  power  of  whose 
minds  affords  us  the  very  liighest  estimate  of  human 
faculties,  the  accuracy  of  whose  calculations  is  hourly 
visible  to  us,  have  affirmed  that  light  emanates  from 
celestial  bodies  at  such  vast  distance,  that  thousands 
of  years  shall  elapse  during  its  progress  to  our  earth : 
yet  matter  impelled  by  a force  equal  to  its  transmission 
through  this  space,  shall  enter  the  eye,  and  strike 
upon  the  delicate  nerve  with  no  other  effect  than  to 
produce  vision. 

Instead  of  saying  that  light  is  created  for  the  eye, 
and  to  give  us  the  sense  of  vision,  is  it  not  more  con- 
formable to  a just  manner  of  considering  these  things 
that  our  wonder  and  our  admiration  should  fix  on  the 
fact,  that  this  small  organ,  the  eye,  is  formed  with 
relation  to  a creation  of  such  vast  extent  and  gran- 
deur : — and  more  especially,  that  the  ideas  arising  in 
the  mind  through  the  influence  of  that  matter  and 
this  organ,  are  constituted  a part  of  this  vast  whole  ! 

By  such  considerations  we  are  led  to  contemplate 
the  human  body  in  its  different  relations.  The  mag- 
nitude of  the  earth  determines  the  strength  of  our 
bones,  and  the  power  of  our  nruscles ; so  must  the 
depth  of  the  atmosphere  determine  the  condition  of 
our  fluids,  and  the  resistance  of  our  blood  vessels  ; the 
common  act  of  breathing,  the  transpiration  from  the 
surfaces,  must  bear  relation  to  the  weight,  moisture, 
and  temperature  of  the  medium  which  surrounds  us. 
A moment’s  reflection  on  these  facts  proves  to  us  that 
our  body  is  formed  with  a just  correspondence  to  all 
these  external  influences. 

These  views  lead  us  to  another  consideration,  that 
the  complexity  of  our  structure  belongs  to  external 
nature,  and  not  of  necessity  to  the  mind.  Whilst 
man  is  an  agent  in  a material  world,  and  sensible  to 
the  influence  of  things  external,  complexity  of  struc- 
ture is  a necessary  part  of  his  constitution.  But  we 
do  not  perceive  a relation  between  this  complexity 


20 


INTRODUCTORY  CHAPTER. 


and  the  mind.  From  aught  that  we  learn  by  this 
mode  of  study,  the  mind  may  be  as  distinct  from  the 
bodily  organs  as  are  the  exterior  influences  which  give 
them  exercise. 

Something,  then,  we  observe  to  be  common  to  our 
planet  and  to  others,  to  our  system  and  to  other  sys- 
tems ; matter,  attraction,  light ; which  nearly  implies 
that  the  mechanical  and  chemical  laws  must  be  the 
same  throughout.  It  is  perhaps  too  much  to  affirm, 
with  an  anonymous  author,  that  an  inhabitant  of  our 
world  would  find  himself  at  home  in  any  other,  that 
he  would  be  like  a traveller  only,  for  a moment  per- 
plexed by  diversity  of  climate  and  strangeness  of  man- 
ners, and  confess,  at  last,  that  nature  was  every  where 
and  essentially  the  same.  However  this  may  be,  all 
I contend  for  is,  the  necessity  of  certain  relations  being 
established  between  the  planet  and  the  frames  of  all 
which  inhabit  it ; between  the  great  mass  and  the 
physical  properties  of  every  pait ; that  in  the  mecha- 
nical construction  of  animals,  as  in  their  endowments 
of  life,they  are  created  in  relation  to  the  whole,  planned 
together  and  fashioned  by  one  Mind. 

The  passiveness  which  is  natural  in  infancy,  and 
the  want  of  reflection  as  to  the  sources  of  enjoymeni 
which  is  excusable  in  youth,  become  insensibility  and 
ingratitude  in  riper  j'ears.  In  the  early  stages  of  life, 
before  our  minds  have  the  full  power  of  comprehen- 
sion, the  objects  around  us  serve  but  to  excite  and 
exercise  the  outward  senses.  But  in  the  maturity  of 
reason,  philosophy  should  present  these  things  to  us 
anew,  with  this  difference,  that  the  mind  may  contem- 
plate them  : that  mind  which  is  now  strengthened  by 
experience  to  comprehend  them,  and  to  entertain  a 
grateful  sense  of  them. 

It  is  this  sense  of  gratitude  which  distinguishes  man. 
In  brutes,  the  attachment  to  offspring  for  a limited 
period  is  as  strong  as  in  him,  but  it  ceases  with  the 
necessity  for  it.  In  man,  on  the  contrary  the  aflections 


INTRODUCTORY  CHAPTER. 


21 


continue,  become  the  sources  of  all  the  endearing  re- 
lations of  life,  and  the  very  bonds  by  which  society  is 
connected. 

If  the  child,  upon  the  parent’s  knee,  is  uncon- 
sciously incurring  a debt,  and  strong  affections  grow 
up  so  naturally  that  nothing  is  more  universally  con- 
demned than  filial  ingratitude,  we  have  but  to  change 
the  object  of  affection,  to  find  the  natural  source  of 
religion  itself.  We  must  show  that  the  care  of  the 
most  tender  parent  is  in  nothing  to  be  compared  with 
those  provisions  for  our  enjoyment  and  safety,  which 
it  is  not  only  beyond  the  ingenuity  of  man  to  provide, 
but  which  he  can  hardly  comprehend,  while  he  pro- 
fits by  them. 

If  man,  of  all  living  creatures,  be  alone  capable  of 
gratitude,  and  through  this  sense  be  capable  also  of 
religion,  the  transition  is  natural ; since  the  gratitude 
due  to  parents  is  abundantly  more  owing  to  Him  “ who 
“saw  him  in  his  blood,  and  said.  Live.” 

For  the  continuance  of  life,  a thousand  provisions 
are  made.  If  the  vital  actions  of  a man’s  frame  were 
directed  by  his  will,  they  are  necessarily  so  minute  and 
complicated,  that  they  would  immediately  fall  into 
confusion.  He  cannot  draw  a breath,  without  the 
exercise  of  sensibilities  as  well  ordered  as  those  of  the 
eye  or  ear.  A tracery  of  nervous  cords  unites  maii}- 
organs  in  sympathy,  of  which,  if  one  filament  were 
broken,  pain  and  spasm,  and  suffocation  would  ensue. 
The  action  of  his  heart,  and  the  circulation  of  his  blood, 
and  all  the  vital  functions  are  governed  through  means 
and  by  laws  which  are  not  dependant  on  his  will,  and 
to  which  the  powers  of  his  mind  are  altogether  inade- 
quate. For  had  they  been  under  the  influence  of  his 
will,  a doubt,  a moment’s  pause  of  irresolution,  a for- 
getfulness of  a single  action  at  its  appointed  time, 
would  have  terminated  his  existence. 

Now,  when  man  sees  that  his  vital  operations  could 
not  be  directed  by  reason — that  they  are  constant,  and 
far  too  important  to  be  exposed  to  all  the  changes 


22 


INTRODUCTORY  CHAPTER. 


iiicideut  to  liis  mind,  and  that  they  are  given  up  to 
the  direction  of  other  sources  of  motion  than  the  will, 
he  acquires  a full  sense  of  his  dependance.  If  man 
be  fretful  and  wayward,  and  subject  to  inordinate  pas- 
sion, we  perceive  the  benevolent  design  in  withdraw- 
ing the  \dtal  motions  from  the  influence  of  such  capri- 
cious sources  of  action,  so  that  they  may  neither  be 
disturbed  like  his  moral  actions,  nor  lost  in  a moment 
of  despair. 

Ray,  in  speaking  of  the  first  drawing  of  breath, 
delivers  himself  very  naturally  : “ Here,  methinks, 
“ appears  a necessity  of  bringing  in  the  agenc}’  oi 
“ some  superintendant  intelligent  being,  for  what  else 
“ should  put  the  diaphragm  and  the  muscles  serving 
“ respiration  in  motion  all  of  a sudden  so  soon  as  ever 
“ the  foetus  is  brought  forth  1 Why  could  they  not 
“ have  rested  as  well  as  they  did  in  the  womb  ? 
“ What  aileth  them  that  they  must  needs  bestir  them- 
“ selves  to  get  in  air  to  maintain  the  creature’s  life  1 
“Why  could  they  not  patiently  suffer  it  to  diel  lou 
“ will  say  the  spirits  do  at  this  time  flow  to  the  or- 
“ gans  of  respiration,  the  diaphragm,  and  other  mus- 
“ cles  which  concur  to  that  action  and  move  them. 
“ But  what  raises  the  spirits  winch  were  quiescent, 
“ &c.,  I am  not  subtile  enough  to  discover.” 

We  cannot  call  this  agency,  a new  intelligence 
different  from  the  mind,  because,  independently  of 
consciousness,  we  can  hardly  so  define  it.  But  there 
is  bestowed  a sensibility,  which  being  roused  (audit  is 
excited  by  the  state  of  the  circulation,)  governs  these 
muscles  of  respiration,  and  ministers  to  life  and  safety, 
independently  of  the  will. 

When  man  thus  perceives,  that  in  respect  to  all 
these  vital  operations  he  is  more  helpless  than  the 
infant,  and  that  his  boasted  reason  can  neither  give 
them  order  nor  protection,  is  not  his  insensibility  to  the 
Giver  of  these  secret  endowments  worse  than  ingrati- 
tude? In  a rational  creature,  ignorance  of  his  condi- 
tion becomes  a species  of  ingratitude  ; it  dulls  his  seiise 


INTRODUCTORY  CHAPTER. 


23 


of  benefits,  and  hardens  him  into  a temper  of  mind  with 
which  it  is  impossible  to  reason,  and  from  which  no 
improvement  can  be  expected. 

Debased  in  some  measure  by  a habit  of  inattention, 
and  lost  to  all  sense  of  the  benevolence  of  the  Crea- 
tor, he  is  roused  to  reflection  only  by  overwhelming- 
calamities,  which  appear  to  him  magnified  and  dis- 
proportioned  ; and  hence  arises  a conception  of  the 
Author  of  his  being  more  in  terror  than  in  love. 

There  is  inconsistency  and  something  of  the  child’s 
propensities  still  in  mankind.  A piece  of  mechanism, 
as  a watch,  a barometer,  or  a dial,  will  fix  attention — 
a man  will  make  journeys  to  see  an  engine  stamp  a 
coin,  or  turn  a block  ; yet  the  organs  through  which 
he  has  a thousand  sources  of  enjoyment,  and  which 
are  in  themselves  more  exquisite  in  design  and  more 
curious  both  in  contrivance  and  in  mechanism,  do  not 
enter  his  thoughts  ; and  if  he  admire  a living  action, 
that  admiration  will  probably  be  more  excited  by  what 
is  uncommon  and  monstrous,  than  by  what  is  natural 
and  perfectly  adjusted  to  its  office — by  the  elephant’s 
trunk,  than  by  the  human  hand.  This  does  not  arise 
from  an  unwillingness  to  contemplate  the  superiority 
or  dignity  of  our  own  nature,  nor  from  an  incapacity 
of  admiring  the  adaptation  of  parts.  It  is  the  effect  of 
habit.  The  human  hand  is  so  beautifully  formed,  it 
has  so  fine  a sensibility,  that  sensibility  governs  its 
motions  so  correctly,  every  effort  of  the  will  is  an- 
swered so  instantly,  as  if  the  hand  itself  were  the  seat 
of  that  will ; its  actions  are  so  powerful,  so  free,  and 
yet  so  delicate,that  it  seems  to  possess  a quality  instinct 
in  itself,  and  there  is  no  thought  of  its  complexity  as 
an  instrument,  or  of  the  relations  which  make  it  sub- 
servient to  the  mind ; we  use  it  as  we  draw  our  breath, 
unconsciously,  and  have  lost  all  recollection  of  the 
feeble  and  ill-directed  efforts  of  its  first  exercise,  by 
which  it  has  been  perfected.  Is  it  not  the  very  per- 
fection of  the  instrument  which  makes  us  insensible 


24 


INTRODUCTORY  CHAPTER. 


to  its  use  1 A vulgar  admiration  is  excited  by  seeing 
the  spider-monkey  pick  up  a straw,  or  a piece  of  wood, 
with  its  tail ; or  the  elephant  searching  the  keeper’s 
pocket  with  his  trunk.  Now,  fidly  to  examine  the 
peculiarity  of  the  elephant’s  structure,  that  is  to  say, 
from  its  huge  mass,  to  deduce  the  necessity  for  its 
form,  and  from  the  form  the  necessity  for  its  trunk, 
would  lead  us  through  a train  of  very  curious  obser- 
vations, to  a more  correct  notion  of  that  appendage, 
and  therefore  to  a truer  admiration  of  it.  But  I take 
this  part  in  contrast  with  the  human  hand,  merely  to 
show  how  insensible  we  are  to  the  perfections  of  our 
own  frame,  and  to  the  advantages  attained  through 
such  a form.  We  use  the  limbs  without  being  con- 
scious, or,  at  least,  without  any  conception  of  the  thou- 
sand parts  which  must  conform  to  a single  act.  To 
excite  our  attention,  we  must  either  see  the  actions  of 
the  human  frame  performed  in  some  mode,  strange 
and  unexpected,  such  as  may  raise  the  wonder  of  the 
ignorant  and  vulgar  ; or  by  an  effort  of  the  cultivated 
mind,  we  must  rouse  ourselves  to  observe  things  and 
actions,  of  which,  as  we  have  said,  the  sense  has  been 
lost  by  long  familiarit3^ 

In  the  following  essa}’,  I shall  take  up  the  subject 
comparatively,  and  exhibit  a \new  of  the  bones  of  the 
arm,  descending  from  the  human  hand  to  the  fin  of  the 
fish.  I shall  in  the  next  place  review  the  actions  of 
the  muscles  of  the  arm  and  hand  ; then  proceeding  to 
the  vital  properties,  I shall  advance  to  the  subject  of 
sensibility,  leading  to  that  of  touch ; afterwards,  I shall 
show  the  necessity  of  combining  tire  muscular  actioir 
with  the  exercise  of  the  senses,  and  especialh’  with 
tliat  of  touch,  to  constitute  in  the  hand  what  has  been 
called  the  geometrical  sense. 

I shall  describe  the  organ  of  touch,  the  cuticle  and 
skin,  and  arrange  the  nerves  of  the  hand  according  to 
their  functions.  I shall  then  enquire  into  the  corre- 
spondence between  the  capacities  and  endowments 
of  the  mind,  in  comparison  with  the  external  organs. 


INTRODUCTORY  CHAPTER. 


and  more  especially  with  the  properties  of  the  hand  ; 
and  conclude  hy  showing  that  animals  have  been 
created  with  a reference  to  the  globe  they  inhabit ; 
that  aU  their  endowments  and  various  organization 
bear  a relation  to  their  state  of  existence,  and  to  the 
elements  around  them  ; that  there  is  a plan  universal, 
extending  through  all  animated  nature,  and  which 
has  prevailed  in  the  earliest  condition  of  the  world  ; 
and  that,  finally,  in  the  most  minute  or  most  compre- 
hensive study  of  those  things  we  every  where  see 
prospective  design. 


3 


CHAPTER  II. 


We  ought  to  define  the  hand  as  belonging  exclu- 
sively to  man — corresponding  in  sensibility  and  mo- 
tion with  that  ingenuity  which  converts  the  being  who 
is  the  weakest  in  natural  defence,  to  the  ruler  over 
animate  and  inanimate  nature. 

If  we  describe  the  hand  as  that  extremity  which 
has  the  thumb  and  fingers  opposed  to  each  other,  so 
as  to  form  an  instrument  of  prehension,  we  extend  it 
to  the  quadrumana  or  monkeys.  But  the  possession 
of  four  hands  by  animals  of  that  class  implies  that  we 
include  the  posterior  as  well  as  the  anterior  extremi- 
ties. Now  the  anterior  extremity  of  the  monkey  is  as 
much  a foot  as  the  posterior  extremity  is  a hand  ; 
both  are  calculated  for  their  mode  of  progression, 
climbing,  and  leaping  from  the  branches  of  trees,  just 
as  the  tail  in  some  species  is  converted  into  a hand, 
and  is  as  useful  an  instrument  of  suspension  as  any 
of  the  four  extremities.* 

The  armed  extremities  of  a variety  of  animals  give 
them  great  advantages ; but  if  man  possessed  any 


* The  Coaita,  or  Spider  Monkey,  so  called  from  the  extraordinaiy 
length  of  its  extremities,  and  its  motions.  The  tail  answers  all  the 
purposes  of  a hand,  and  the  animal  throws  itself  about  from  branch 
to  branch,  sometimes  stringing  from  the  foot,  sometimes  by  the  hand, 
but  oftener  and  with  a greater  reach  by  the  tail.  The  prehensile  part 
of  tlie  tail  is  covered  only  with  skin,  forming  an  organ  of  touch,  as 
discriminating  as  the  hand.  The  Caraya,  or  Black  howling  monkey 
of  Cumana,  when  shot,  is  found  suspended  by  its  tail,  round  a branch. 
Naturalists  have  been  so  struck  with  the  property  of  the  tail  of  the 
Ateles,  as  to  compare  it  with  the  proboscis  of  the  elephant ; they  have 
assured  us  that  they  fish  with  it. 

The  most  interesting  use  of  the  tail  is  seen  in  the  Opossum.  The 
young  of  tliat  animal  entwine  their  tails  around  their  mother’s  tail  and 
mount  upon  her  back,  where  they  sit  secure,  while  she  escapes  from 
her  enemies. 


THE  HAND,  ITS  MECHANISM,  ETC. 


27 


similar  provisions,  he  would  forfeit  his  sovereignty 
over  all.  As  Galen,  long  since,  observed,  “ did  man 
“ possess  the  natural  armour  of  the  brutes,  he  would  no 
‘ longer  work  as  an  artificer,  nor  protect  himself  with  a 
“ breast-plate,  nor  fashion  a sword  or  spear,  nor  invent 
“ a bridle  to  mount  the  horse  and  hunt  the  lion.  Kei- 
“ ther  could  he  follow  the  arts  of  peace,  construct  the 
“ pipe  andl}Te,  erect  houses,  place  altars,  inscribe  laws, 
“ and  through  letters  hold  communion  Avith  the  wis- 
“ dom  of  antiquity “ tibique  liceat  literamm  et  ma- 
“ nuum  benejiciis  ctiam  nunc  colloqui  cum  Platone,  cum- 
“ Aristotele,  cum  HippocrateP 

But  the  hand  is  not  a distinct  instrument  ; nor  is 
it  properly  a superadded  part.  The  whole  frame  must 
conform  to  the  hand,  and  act  with  reference  to  it. 
Our  purpose  will  not  be  answered  by  examining  it 
alone  ; we  must  extend  our  views  to  all  those  parts  of 
the  body  Avhich  are  in  strict  connection  with  the  hand. 
For  example,  the  bones  from  the  shoulder  to  the  fin- 
ger ends,  have  that  systematic  arrangement  which 
makes  it  essential  to  examine  the  whole  extremity  ; 
and  in  order  fully  to  comprehend  the  fine  arrange- 
ment of  the  parts,  Avhich  is  necessary  to  the  motions 
of  the  fingers,  we  must  also  compare  the  structure  of 
the  human  body  with  that  of  other  animals. 

Were  we  to  limit  our  enquiry  to  the  bones  of  the 
arm  and  hand  in  man,  no  doubt  we  should  soon  dis- 
cover their  provisions  for  easy,  varied,  and  powerful 
action  ; and  conclude  that  nothing  could  be  more 
perfectly  suited  to  their  purposes.  But  we  must  ex- 
tend our  views  to  comprehend  a great  deal  more,— -a 
greater  design. 

By  a skeleton,  is  understood  the  system  of  bones, 
which  being  internal,  gives  the  characteristic  form  to 
the  animal,  and  receives  the  action  of  the  exterior 
muscles.  This  system  belongs,  however,  only  to  one 
jrart  of  the  animal  kingdom,  that  higher  division, — the 
animalia  vertebrata,  which  includes  the  Avhole  chain 
of  beings,  from  man  to  fishes. 


28 


THE  BONES  OF  THE  EXTREMITY. 


The  function  of  the  greatest  consequence  to  life  is 
respiration  ; and  the  mode  in  which  this  is  perfonned, 
that  is  to  say,  the  manner  in  which  the  decarboniza- 
tion of  the  blood  is  effected  tlnough  its  exposure  to 
tlie  atmosphere,  produces  a remarkable  change  in  the 
whole  frame-work  of  the  animal  body. 

Man,  the  mammalia,  birds,  reptiles,  and  fishes  have 
much  of  the  mechanism  of  respiration  in  common ; 
and  there  is  a resemblance  through  them  all,  in  the 
texture  of  the  bones,  in  the  action  of  the  muscles,  and 
in  the  arrangement  of  the  nerves.  They  all  possess 
the  vertebral  column  or  spine ; and  the  existence  of 
this  column,  not  only  implies  an  internal  skeleton,  but 
that  particular  frame-work  of  ribs,  which  is  suited  to 
move  in  breathing.  But  the  ribs  do  not  move  of  them- 
selves, they  must  have  appropriate  muscles ; and  these 
muscles  must  have  their  appropriate  nerves ; and  for 
supplying  these  nerves  there  must  be  a spinal  mar- 
row. The  spinal  canal  is  as  necessar}"  to  the  spinal 
marrow  as  the  skull  is  to  the  brain.  So  that  we  come 
round  to  understand  the  necessity  of  a vertebra,  to  the 
formation  of  the  spinal  marrow  ; and  the  reader  may 
comprehend  how  much  enters  into  the  conception  of 
the  anatomist  or  naturalist,  wlien  the  term  is  used,  a 
vertebrated  animal,  viz  : — an  internal  skeleton,  a par- 
ticular arrangement  of  respiratory  organs,  and  a con- 
formity in  the  nervous  system. 

It  is  to  this  superior  division  that  I shall  limit  myself, 
in  making  a review  of  the  bones  of  the  upper  extremity. 

Were  I to  indulge  in  the  admiration  naturally  aris- 
ing out  of  this  subject,  and  point  out  the  strength  and 
the  freedom  of  motion  in  the  upper  extremity  at  the 
ball  and  socket  joint  of  the  shoulder, — the  firmness  of 
the  articulation  of  the  elbow,  and  yet  how  admirably  it 
is  suited  to  the  co-operation  of  the  hands, — the  fine- 
ness of  the  motion  of  the  hand  itself,  divided  among 
the  ioints  of  twenty-nine  bones,  it  might  be  objected 
to  with  some  show  of  reason ; and  it  might  be  said, 
the  bones  and  the  forms  of  the  joints  which  you  are 


NOT  ADAPTED  TO  MAN  ALONE. 


29 


admiring,  are  so  far  from  being  peculiarly  suited  to 
the  hand  of  man,  that  they  may  be  found  in  any 
other  vertebrated  animal. 

But  this  would  not  abate  our  admiration,  it  would 
only  induce  us  to  take  a more  comprehensive  view  of 
nature,  and  remind  us  that  our  error  was  in  looking  at 
a part  only,  instead  of  embracing  the  whole  system  ; 
where  by  slight  changes  and  gradations  hardly  per- 
ceptible, the  same  bones  are  adjusted  to  every  condi- 
tion of  animal  existence. 

We  recognize  the  bones  which  form  the  upper  ex- 
tremity of  man,  in  the  fin  of  the  whale,  in  the  paddle 
of  the  turtle,  and  in  the  wing  of  the  bird.  We  see  the 
same  bones,  perfectly  suited  to  their  purpose,  in  the 
paw  of  the  lion  or  the  bear,  and  equally  fitted  for  mo- 
tion in  the  hoof  of  the  horse,  or  in  the  foot  of  the  camel, 
or  adjusted  for  climbing  or  digging  in  the  long  clawed 
feet  of  the  sloth  or  bear. 

It  is  obvious,  then,  that  we  should  be  occupied  with 
too  limited  a view  of  our  subject,  were  we  to  consider 
the  human  hand  in  any  other  light  than  as  present- 
ing the  most  perfect  combination  of  parts  : as  exhibit- 
ing the  parts,  which  in  different  animals  are  suited  to 
particular  purposes,  so  combined  in  the  hand,  as  to 
perform  actions  the  most  minute  and  complicated, 
consistently  with  powerful  exertion. 

The  wonder  still  is,  that  whether  we  examine  this 
system  in  man,  or  in  any  of  the  inferior  species  of  ani- 
mals, nothing  can  be  more  curiously  adjusted  or  ap- 
propriated ; and  we  should  be  inclined  to  say,  what- 
ever instance  occupied  our  thoughts  for  the  time,  that 
to  this  particular  object  the  system  had  been  framed. 

The  view  which  the  subject  opens  to  us,  is  un- 
bounded. The  curous  synthesis  by  which  we  ascer- 
tain the  nature,  condition,  and  habits  of  an  extinct 
animal,  from  the  examination  of  its  fossil  remains,  is 
grounded  on  a knowledge  of  the  system  of  which  we 
are  speaking.  A bone  consists  of  many  parts ; but 
for  our  present  purpose  it  is  only  necessary  to  observe 
3+ 


30 


FOSSILIZED  BONES  SHOW 


that  the  hard  substance,  the  phosphate  of  lime,  whicli 
we  familiarly  recognize  as  bone,  is  everywhere  pene- 
trated by  membranes  and  vessels  as  delicate  as  those 
which  belong  to  any  other  part  of  the  body.  Some 
bones  are  found  with  their  animal  part  remaininsr, 
others  are  fossilized.  Tire  phosphate  of  lime  loses  its 
phosphoric  acid,  and  the  earth  of  bone  remains  incor- 
ruptible, while  the  softer  animal  matter  undergoes  the 
process  of  decomposition,  and  is  dissipated.  The  bone 
in  this  condition  may  become  fossilized ; silicious  earth, 
or  lime  in  composition  with  iron,  or  iron  pyrites,  may 
pass  by  infiltration  into  the  interstices  of  the  original 
earthy  matter,  and  in  this  state  it  is  as  permanent  as 
the  solid  rock.  It  retains  the  form,  though  not  the 
internal  structure  of  bone  ; and  that  form,  in  conse- 
quence of  the  perfect  system  which  we  have  hinted 
at,  becomes  a proof  of  revolutions  the  most  extraordi- 
nar}L  The  mind  of  the  enquirer  is  carried  back,  not 
merely  to  the  contemplation  of  animal  structure,  but 
by  inference,  from  the  system  of  animal  organization 
to  the  structure  of  the  globe  itself. 

The  bones  of  large  animals  and  in  great  variety 
are  found  imbedded  in  the  surface  of  the  earth. 
They  are  discovered  in  the  beds  of  rivers,  they  are 
found  where  no  waters  flow,  they  are  dug  up  from 
under  the  solid  limestone  rock.  The  bones  thus 
exposed,  become  naturally  a subject  of  intense  in- 
terest, and  are  unexpectedly  connected  with  the  en- 
quiry in  which  we  are  engaged.  Among  other  im- 
portant conclusions  they  lead  to  this — that  there  is 
not  only  a scheme  or  system  of  animal  structure  per- 
vading all  the  classes  of  animals  which  inhabit  the 
earth,  but  that  the  principle  of  this  great  plan  of 
creation  was  in  operation,  and  governed  the  formation 
of  those  animals  which  existed  previous  to  the  revo- 
lutions that  the  earth  itself  has  undergone  : that  the 
excellence  of  form  now  seen  in  the  skeleton  of  man, 
was  in  the  scheme  of  animal  existence  long  previous 
to  the  formation  of  man,  and  before  the  surface  of 


THE  EXTENT  OF  THE  SYSTEM. 


31 


the  earth  was  prepared  for  him  or  suited  to  his  consti- 
tution, structure,  or  capacities. 

A skeleton  is  dug  up  which  has  lain  under  many 
fathoms  of  rock  : being  the  bones  of  an  animal 
which  lived  antecedent  to  that  formation  of  rock,  and 
at  a time  when  the  earth’s  surface  must  have  been  in 
a condition  very  different  from  what  it  is  now.  These 
remains  prove,  that  all  animals  have  been  formed  of 
the  same  elements,  and  have  had  analogous  organs 
— that  they  received  new  matter  by  digestion,  and 
were  nourished  by  means  of  a circulating  fluid — that 
they  possessed  feeling  through  a nervous  system,  and 
were  moved  by  the  action  of  muscles — that  their  or- 
gans of  digestion,  circulation,  and  respiration  were 
modified  by  circumstances,  as  in  the  animals  now  alive, 
and  in  accordance  with  their  habits  and  modes  of  liv- 
ing. The  changes  in  the  organs  are  l3ut  variations  in 
the  great  system  by  which  new  matter  is  assimilated 
to  the  animal  body, — and  however  remarkable  these 
may  be,  they  always  bear  a certain  relation  to  the 
original  type  as  parts  of  the  same  great  design. 

In  examining  these  bones  of  the  ancient  world,  so 
regularly  are  they  formed  on  the  same  principle  which 
is  evident  in  the  animals  now  inhabiting  the  earth, 
that  on  observing  their  shape,  and  the  processes  by 
which  their  muscles  were  attached,  we  can  reduce 
the  animals  to  which  they  belonged,  to  their  orders, 
genera,  and  species, with  as  much  precision  as  if  the  re- 
cent bodies  had  been  submitted  to  the  eye  of  the  ana- 
tomist. Not  only  can  we  demonstrate  that  their  feet 
were  adapted  to  the  solid  ground,  or  to  the  oozy  bed 
of  rivers, — for  speed,  or  for  grasping  and  tearing  ; but 
judging  by  these  indications  of  the  habits  of  the  ani- 
mals, we  acquire  a knowledge  of  the  condition  of  the 
earth  during  their  period  of  existence  ; that  it  was 
suited  at  one  time  to  the  scaly  tribe  of  the  lacertee, 
until  languid  motion ; at  another,  to  animals  of  higher 
organization,  with  more  varied  and  lively  habits  ; and 
finally  we  learn,  that  at  any  period  previous  to  man’s 


32 


ANIMALS  THE  MOST  UNCOUTH 


creation,  the  surface  of  the  earth  would  have  been 
unsuitable  to  him. 

On  comparing  some  of  the  present  races  of  animals, 
with  the  fossil  remains  of  individuals  of  the  same 
family,  some  singular  opinions  on  their  imperfections 
have  been  expressed  by  Buffon,  and  adopted  by  Cu- 
vier. The  animals  I allude  to  are  of  the  tardigrade 
family  ; the  Ai,*  in  which,  as  they  believe,  the  defect 
of  organizaton  is  the  greatest ; and  the  Unau,f  which 
they  consider  only  a little  less  miserably  provided  for 
existence. 

Modern  travellers  express  their  pit}*  for  these  ani- 
mals : whilst  other  quadrupeds,  they  sa}*,  range  in 
boundless  wilds,  the  sloth  hangs  suspended  by  his 
strong  arms — a poor  ill-formed  creature,  deficient  as 
well  as  deformed,  his  hind  legs  too  short,  and  his  hair 
like  withered  grass  ; his  looks,  motions,  and  cries  con- 
spire to  excite  pity  ; and,  as  if  this  were  not  enough, 
they  say  that  his  moaning  makes  the  tiger  relent  and 
turn  away.  This  is  not  a true  picture : the  sloth  cannot 
walk  like  quadrupeds,  but  he  stretches  out  his  strong 
arms, — and  if  he  can  hook  on  his  claws  to  the  ine- 
qualities of  the  ground,  he  drags  himself  along.  This 
is  the  condition  which  authorizes  such  an  expression 
as  “ the  bungled  and  faulty  composition  of  the  sloth.” 
But  when  he  reaches  the  branch  or  the  rough  bark  of 
a tree,  his  progress  is  rapid  ; he  chmbs  hand  over 
head,  along  the  branches  till  they  touch,  and  thus 
from  bough  to  bough,  and  from  tree  to  free  ; he  is 
most  alive  in  the  storm,  and  when  the  wmd  blows,  and 
the  trees  stoop,  and  the  branches  wave  and  meet,  he  is 
then  upon  the  march. 

The  compassion  expressed  by  these  philosopher.^- 
for  animals,!  which  they  consider  imperfectly  organ- 

* Bradypus  Tridaclylus : — bradypus  (ship  footed,)  tridactylus  (three 
toed,)  of  the  order  Edentata  (ipanting  incisor  teeth.) 

I Bradypus  didactylus. 

j The  subject  is  pursued  in  the  end  of  tlie  following  chapter. 


SUITED  TO  THEIR  CONDITION. 


33 


ized,  is  uncalled  for  ; as  well  miglit  they  pity  the 
larva  of  the  summer  fly,  which  creeps  in  the  bottom 
of  a pool,  because  it  cannot  yet  rise  upon  the  wing. 
As  the  insect  has  no  impulse  to  fly  until  the  meta- 
morphosis is  perfect,  and  the  wings  developed,  so  we 
have  no  reason  tosuppose  that  a disposition  or  instinct 
is  given  to  animals,  where  there  is  no  corresponding 
provision  for  motion. 

The  sloth  may  move  tardily  on  the  ground,  his  long 
arms  and  his  preposterous  claws  may  be  an  incum- 
brance, but  they  are  of  advantage  in  his  natural  place, 
among  the  branches  of  trees,  in  obtaining  his  food, 
and  in  giving  him  shelter  and  safety  from  his  ene- 
mies. 

We  must  not  estimate  the  slow  motions  of  animals 
by  our  own  sensations.  The  motion  of  the  bill  of  the 
swallow,  or  the  fly-catcher,  in  catching  a fly,  is  so  ra- 
pid that  we  do  not  see  it,  but  only  hear  the  snap.  On 
the  contrary,  how  very  different  are  the  means  given 
to  the  chamelion  for  obtaining  his  food  ; he  lies  more 
still  than  the  dead  leaf,  his  skin  is  like  the  bark  of 
the  tree,  and  takes  the  hue  of  surrounding  objects. 
Whilst  other  animals  have  excitement  conforming  to 
their  rapid  motions,  the  shrivelled  face  of  the  chaine- 
lion  hardly  indicates  life  ; the  eyelids  are  scarcely 
parted  ; he  protrudes  his  tongue  with  a motion  so 
imperceptible  towards  the  insect,  that  it  is  touched 
and  caught  more  certainly  than  by  the  most  lively 
action.  Thus,  various  creatures  living  upon  insects, 
reach  their  prey  by  different  means  and  instincts  ; 
rapidity  of  motion,  which  gives  no  time  for  escape,  is 
bestowed  on  some,  while  others  have  a languid  and 
slow  movement  that  excites  no  alarm. 

The  loris,  a tardigrade  animal,  might  be  pitied  too 
for  the  slowness  of  its  motions,  if  they  were  not  the 
very  means  bestowed  upon  it  as  necessary  to  its 
existence.  It  steals  on  its  prey  by  night,  and  ex- 
tends its  arm  to  the  bird  on  the  branch,  with  a 
motion  so  imperceptibly  slow,  as  to  make  sure  of  its 


34 


MISTAKEN  COMPASSION  FOR 


object."^  Just  SO,  the  Indian  perfectly  naked,  his  hair 
cut  short,  and  his  skin  oiled,  creeps  under  the  canvass 
of  the  tent,  and  moving  like  a ghost,  stretches  out  his 
hand,  with  so  gentle  a motion  as  to  displace  nothing, 
and  to  disturb  not  even  those  who  are  awake  and 
watching.  Against  such  thieves,  we  are  told,  that  it 
is  hardly  possible  to  guard  ; and  thus,  the  necessities 
or  vicious  desires  of  man  subjugate  him,  and  make 
him  acquire,  by  practice,  the  wiliness  which  is  im- 
planted as  instinct  in  brutes  ; or  we  may  say  that 
in  our  reason  we  are  brought  to  imitate  the  iiTational 
creatures,  and  so  to  vindicate  the  necessity  for  their 
particular  instincts,  of  which  every  class  affords  an 
instance.  We  have  examples  in  insects,  as  striking 
as  in  the  loris  or  the  chamelion.  Evelyn  describes 
the  actions  of  the  spider  {aranea  scenica)  as  exhibiting 
remarkable  cunning  in  catching  a fly.  “ Did  the 

fly,  (he  says,)  happen  not  to  be  within  a leap,  the 
“ spider  would  move  towards  it,  so  soft!}',  that  its 
“ motion  seemed  not  more  perceptible  than  that  of 
“ the  shadow  of  the  gnomon  of  a dial.”f 

I would  only  remark  further  on  tlrese  slow  motions 

* For  our  purpose,  it  may  be  well  to  notice  other  characters  of  this 
and  similar  animals  which  prowl  by  night.  They  are  inhabitants  of 
the  tropical  regions.  Now,  the  various  creatures  which  enliven  the 
woods  in  the  day-time,  in  these  warm  climates,  have  fine  skins,  and 
smooth  hair;  but  those  have  a coat  like  animals  of  the  arctic  regions. 
What  is  this,  but  to  clothe  them,  as  the  sentinel  is  clothed,  whose 
watch  is  in  the  night.  They  have  eyes  too,  which,  from  their  peculiari- 
ty, are  called  nocturnal,  being  fonned  to  admit  a greater  pencil  of  rays. 
For  this  purpose  the  globe  is  large  and  prominent,  and  the  iris  con- 
tractile, to  open  the  pupil  to  the  greatest  extent. — We  have  seen 
how  all  their  motions  and  instincts  correspond  with  their  noctunial 
habits. 

t The  passage  continues — “if  the  intended  prey  moved,  the  spider 
would  keep  pace  with  it  exactly  as  if  the}-  were  actuated  by  one  spirit, 
moving  backwards,  forwards,  or  on  each  side  without  turning.  When 
the  fly  took  v\ung,  and  pitched  itself  behind  the  huntress,  she  turned 
round  viuth  the  swiftness  of  thought,  and  always  kept  her  head  to- 
wards it,  though  to  all  appearance  as  immoveable  as  one  of  the  nails 
driven  into  the  wood  on  wliich  was  her  station ; till  at  last,  beinc  ar- 
rived within  due  distance,  swift  as  lightning  she  made  the  fktalleap, 
and  secured  her  prey.” — ^Eveh-n,  as  quoted  by  Kirby  and  Spence. 


ANIMALS  OF  PECULIAR  FORM. 


35 


of  the  muscles  of  animals ; that  we  are  not  to  ac- 
count this  a defect,  but  rather  an  appropriation  of 
muscular  power.  Since  in  some  animals  the  same 
muscles  which  move  their  members  in  a manner  to 
be  hardly  perceptible,  can  at  another  time  act  with 
the  velocity  of  a spring-. 

Now  Buffon,  speaking  of  the  extinct  species  of  the 
tardigrade  family,  considers  them  as  monsters  by  de- 
fect of  organization  ; as  attempts  of  nature  in  which 
she  has  failed  to  perfect  her  plan  ; that  she  has  pro- 
duced animals  wliich  must  have  lived  miserably,  and 
which  are  effaced  as  failures  from  the  list  of  living 
beings.  The  Baron  Cuvier  does  not  express  himself 
more  favorably,  when  he  says  of  the  existing  species, 
that  they  have  so  little  resemblance  to  the  organiza- 
tion of  animals  generally,  and  their  structure  is  so 
much  in  contrast  with  that  of  other  creatures,  that 
he  could  believe  them  to  be  the  remnants  of  an  order 
unsuitable  to  the  present  system  of  nature  ; and  if  we 
are  to  look  for  their  congeners,  it  must  be  in  the  inte- 
rior of  the  earth,  in  the  ruins  of  the  ancient  world. 

The  animals  of  the  Antediluvian  world  were  not 
monsters ; there  was  no  lusus  or  extravagance. 
Hideous  as  they  appear  to  us,  and  like  the  phantoms 
of  a dream,  they  were  adapted  to  the  condition  of  the 
earth  when  they  existed.  I could  have  wished  that 
our  naturalists  had  given  the  inhabitants  of  that  earh' 
condition  of  the  globe,  names  less  scholastic.  We 
have  the  plesiosaurus,  and  plesiosaurus  dolichodeirus, 
we  have  the  ichthyosaurus  and  megalosaurus,  and 
iguanodon,  pterodactyles,  with  long-  and  short  beaks, 
tortoises,  and  crocodiles  ; and  these  are  found  among 
reeds  and  grasses  of  gigantic  proportions,  alga)  and 
fuel,  and  a great  variety  of  mollusca  of  inordinate 
bulk,  compared  with  those  of  the  present  day,  as  am- 
monites and  nautili.  Every  thing  declares,  that 
these  animals  inhabited  shallow  seas,  and  estuaries, 
or  great  inland  lakes : that  the  surface  of  the  eartli 
did  not  rise  up  in  peaks  and  mountains,  or  that  per- 


36 


MAN  SUITED  TO  THE  PRESENT. 


pendiciilar  rocks  bound  in  the  seas ; but  that  it  was 
flat,  slimy,  and  covered  with  a loaded  and  foggy 
atmosphere.  There  is,  indeed,  every  reason  to  believe 
that  the  classes  mammalia  and  birds  were  not  then 
created  , and  that  if  man  had  been  placed  in  this  con- 
dition of  ihe  earth,  there  must  have  been  around  him 
a state  of  things  unsuited  to  his  constitution,  and  not 
calculated  to  call  forth  his  capacities. 

But  looking  to  the  class  of  animals  as  we  have 
enumerated  them,  there  is  a correspondence  ; the}' 
were  scaly ; they  swam  in  water,  or  crept  upon  the 
margins  ; there  were  no  animals  possessed  of  rapidity 
of  motion,  and  no  birds  of  prey  to  stoop  upon  them  ; 
there  was,  in  short,  that  balance  of  the  power  of 
destruction  and  of  self  preservation,  which  we  see 
now  to  obtain  in  higher  animals  since  created,  with 
infinitely  varied  instincts  and  powers  for  defence  or 
attack. 

It  is  hardly  possible  to  watch  the  night  and  see  the 
break  of  day  in  a fine  country,  without  being  sensible 
that  our  pleasantest  perceptions  refer  to  the  scenery 
of  nature,  and  that  we  have  feelings  in  sympathy 
with  every  successive  change,  from  the  first  streak  of 
light,  until  the  whole  landscape  is  displayed  in  val- 
leys, woods,  and  sparkling  waters  ; and  the  changes 
on  the  scene  are  not  more  rapid  than  the  transitions 
of  the  feelings  which  accompany  them.  All  these 
sources  of  enjoyment,  the  clear  atmosphere  and 
the  refreshing  breezes,  are  as  certainly  the  result  of 
tlie  several  changes  which  the  earth’s  surface  has 
undergone,  as  the  displaced  strata  within  its  crust 
are  demonstrative  of  these  changes.  e have  eveiy 
reason  to  conclude  that  these  revolutions,  whether 
they  have  been  slowl}"  accomplished  and  progressively 
or  by  sudden,  vast  and  successive  convulsions,  were 
necessary  to  prepare  the  earth  for  that  condition 
which  should  correspond  with  the  faculties  to  be 
given  to  man,  and  be  suited  to  the  full  exercise  of 
his  reason,  as  well  as  to  his  enjoyment. 


CONDITION  OF  THE  EARTH. 


37 


if  a man  contemplate  the  common  objects  around 
hixn — if  he  observe  the  connection  between  the  quali- 
ties of  things  external  and  the  exercise  of  his  senses, 
between  the  senses  so  excited,  and  the  coiidition  of 
his  mind,  he  will  perceive  that  he  is  in  the  centre  of  a 
magnificent  system,  and  that  the  strictest  relation  is 
established  between  the  intellectual  capacities  and 
the  material  world. 

In  the  succeeding  chapter  we  shall  take  a compa- 
rative view  of  the  anatomy  of  the  arm,  and  we  shall 
be  led  to  observe  some  very  extraordinary  changes, 
as  Ave  trace  the  same  parts  through  different  genera 
and  species  of  animals.  In  doing  this,  we  are  natu- 
rally called  upon  to  notice  certain  opinions  which 
prevail  on  the  subject. 

We  have  already  hinted,  that  geologists  have 
discovered,  that  in  the  stratified  rocks  there  is  proof 
of  a regular  succession  of  formations  in  the  crust  of 
the  earth,  and  that  animals  of  very  clifl’erent  stiuc- 
ture  have  been  imbedded,  and  are  preserved  in  them. 
In  the  earlier  formed  strata  animals  are  found  which 
are  low,  as  we  choose  to  express  it,  in  the  chain  of 
existence ; in  higher  strata,  oviparous  animals  of 
great  bulk,  and  more  complex  structure,  are  disco- 
vered ; above  the  strata  containing  these  oAuparous 
reptiles,  there  are  found  mammalia ; and  in  the 
looser  and  more  superficial  stratum  are  the  bones  of  the 
mastodon,  megatherium,  rhinoceros,  and  elephant, 
&c.  We  must  add  that  geologists  agree  that  man 
has  been  created  last  of  all. 

Upon  these  facts,  a theory  is  raised,  that  there  has 
been  a succession  of  animals  gradually  increasing 
in  the  perfection  of  their  structure  ; that  the  first 
impulse  of  nature  Avas  not  sufficient  to  tlie  produc- 
tion of  the  highest  and  most  perfect,  and  that  it  Avas 
only  in  her  mature  efforts  that  mammalia  Avere  pro- 
duced. We  are  led  to  this  reflection ; that  the 
creation  of  a living  animal,  the  bestoAving  of  life  on  a 
4 


38 


OP  THE  SUCCESSION  AND 


corporeal  frame,  however  simple  the  structure  of  that 
body,  is  of  itself,  an  act  of  creative  power  so  incon- 
ceivably great,  that  we  can  have  no  title  to  presume 
that  the  change  in  the  organization,  such  as  the 
provision  of  bones  and  muscles,  or  the  production  of 
new  organs  of  sense,  is  a higher  effort  of  that  power. 
We  have  a better  guide  in  exploring  the  varieties  of 
animated  nature,  when  we  acknowledge  the  mani- 
fest design  with  which  all  is  accomplished ; the 
adaptation  of  the  animals,  their  size,  their  economy, 
their  organs,  and  instruments  to  their  condition. 

Whether  we  make  the  most  superficial  or  most 
profound  examination  of  animals  in  their  natural 
state,  we  shall  find  that  the  varieties  are  so  balanced 
as  to  ensure  the  existence  of  all.  This,  we  think, 
goes  far  to  explain,  first,  why  the  remains  of  certain 
animals  are  found  in  certain  strata,  which  imply  a 
peculiar  condition  of  the  earth’s  surface ; and,  se- 
condly, why  these  animals  are  found  grouped  toge- 
ther. For,  as  we  may  express  it,  if  there  had  been 
an  error  in  the  groupuig,  there  must  have  been  a 
destruction  of  the  whole ; the  balance  which  is  ne- 
cessary to  their  existence  having  been  destroyed. 
We  know  very  well  that  so  minute  a thing  as  a fly, 
will  produce,  in  twenty-four  hours,  millions,  which, 
if  not  checked,  will  ere  long  darken  the  air,  and  ren- 
der whole  regions  desolate  ; so  that  if  the  breeze  does 
not  carry  them  in  due  time  into  the  desert,  or  into  the 
ocean,  the  destruction  will  be  most  fearful. 

As  in  the  present  day  every  creature  has  its  natural 
enemy  ; or  is  checked  in  production,  sometimes  by  a 
limited  supply  of  food,  sometimes  by  disease,  or  by  the 
influence  of  seasons  ; and  as  in  the  whole  a balance  is 
preserved,  we  may  reasonabl}"  apply  the  same  princi- 
ple in  explanation  of  the  condition  of  things  as  they 
existed  in  the  earher  stages  of  the  world’s  progress ; 
certainl)^,  this  view  is  borne  out,  by  what  we  have  as 
yet  discovered  in  the  grouping  of  animals,  in  the 
d fferent  stratifications  or  deposits  of  the  earth. 


GROUPING  OF  ANIMALS. 


S9 


If  the  naturalist  or  geologist,  exploring  the  rocks 
of  secondary  formation,  should  find  inclosed  within 
them  animals  of  the  class  Molusca,  it  agrees  Avith 
his  preconceived  notions,  that  only  animals  of  their 
simple  structure  were  in  existence,  at  the  time  of  the 
subsidence  of  that  matter  of  which  the  rock  consists. 
But  if  the  spine  of  a fish,  or  a jawbone,  or  a tooth, 
be  discovered,  he  is  much  disturbed,  because,  here  is 
the  indication  of  an  animal  having  been  at  that  time 
formed  on  a different  type, — on  that  plan  which 
belongs  to  animals  of  a superior  class. — Whereas  on 
the  supposition  that  animals  are  created  with  that 
relation  to  circumstances,  which  we  have  just  alluded 
to,  it  would  only  imply  that  certain  animals,  which 
had  hitherto  increased  undisturbed,  had  arrived  at  a 
period,  when  their  numbers  were  to  be  limited ; or 
that  the  condition  of  the  elements  and  the  abundance 
of  food  were  now  suited  to  the  existence  of  a species 
of  the  vertebrate. 

The  principle  then,  in  the  application  of  which  Ave 
shall  be  borne  out,  is,  that  there  is  an  adaptation,  an 
established  and  universal  relation  between  the  in- 
stincts, organization,  and  instruments  of  animals  on 
the  one  hand,  and  the  element  in  which  they  are  to 
live,  the  position  Avhich  they  hold,  and  their  means 
of  obtaining  food  on  the  other ; — and  this  holds  good 
Avith  respect  to  the  animals  Avhich  have  existed,  as 
Avell  as  those  Avhich  noAV  exist. 

In  discussing  this  subject  of  the  progresswe  im- 
provement of  organized  beings,  i t is  affirmed  that  the 
last  created  of  all,  man,  is  not  superior  in  organiza- 
tion to  the  others,  and  that  if  deprived  of  intellectual 
power  he  is  inferior  to  the  brutes.  I am  not  arguing 
to  support  the  gradual  developement  and  improA-e- 
ment  of  brganization ; but,  hoAveA^er  indifferent  to  the 
tendency  of  the  argument,  I must  not  admit  the 
statement.  Man  is  superior  in  organization  to  the 
brutes, — superior  in  strength — in  that  constitutional 
property  Avhich  enables  him  to  fulfil  his  destinies  by 


40 


OF  THE  SUCCESSION  AND 


extending  his  race  in  every  climate,  and  living  on 
every  variety  of  nutriment.  Gather  together  the 
most  powerful  brutes,  from  the  artic  circle  or  torrid 
zone,  to  some  central  point — they  will  die,  diseases 
will  be  generated,  and  will  destroy  them.  With 
respect  to  the  superiority  of  man  being  in  his  mind, 
and  not  merely  in  the  provisions  of  his  bod)',  it  is  no 
doubt  true  ; — but  as  we  proceed,  we  shall  find  how 
the  Hand  supplies  all  instruments,  and  by  its  corres- 
pondence with  the  intellect  gives  him  universal  do- 
minion. It  presents  the  last  and  best  proof  of  that 
principle  of  adaptation,  which  evinces  design  in  the 
creation. 

Another  notion  Avhich  we  meet  with,  is,  that  the 
variety  of  animals  is  not  a proof  of  design,  as  showing 
a relation  between  the  formation  of  their  organs,  and 
the  necessity  for  their  exercise  ; but  that  (he  circum- 
stances in  which  tire  animal  has  been  placed,  have 
been  the  cause  of  the  variety.  The  influence  of 
these  circumstances,  it  is  pretended,  has,  hr  the  long 
progress  of  tune,  produced  a complication  of  structure 
out  of  an  animal  which  was  at  first  simple.  "V^'e 
shall  reserve  the  discussion  of  this  subject  until  we 
have  the  data  before  us  ; Avhich,  of  themselves,  and 
without  much  argument,  will  suflice  to  overthrow  it. 
I may  notice  here  another  idea  of  naturalists,  who 
are  pleased  to  reduce  these  changes  in  the  structure 
of  animals  into  general  laws.  They  affirm  that  in 
the  centre  of  the  animal  body  there  is  no  disposition 
to  change,  Avhilst  in  the  extremities  we  see  siupris- 
ing  variations  of  form.  If  this  be  a law,  there  is  no 
more  to  be  said  about  it,  the  enquiiy  is  terminated. 
But  I contend  that  the  term  is  quite  inapplicable,  and 
worse  than  useless,  as  tending  to  check  enquiry. 
What  then  is  the  meaning  of  this  variation  in  the 
extremities  and  comparative  permanence  towards  the 
centre  of  the  skeleton  1 I conceive  the  rationale  to 
be  this,  that  the  central  part,  by  which  in  fact  they 
mean  the  skull,  spine,  and  ribs,  are  permanent  in 


GROUPING  OF  ANIMALS. 


41 


their  offices  ; whilst  the  extremities  vary  and  are 
adapted  to  every  exterior  circumstance.  The  office 
of  the  back  part  of  the  skull  is  to  protect  the  brain,  that 
of  the  spine  to  contain  the  spinal  marrow,  and  the 
ribs  to  perfonu  respiration.  Why  should  we  expect 
these  parts  to  vary  in  shape  while  their  office  remains 
the  same  1 But  the  shoulder  must  var)'  in  form,  as 
it  does  in  motion.  The  shape  of  the  bones  and  the 
joints  of  the  extremities  must  be  adapted  to  their 
various  actions,  and  the  carpus  and  phalanges  must 
change,  more  than  all  the  rest,  to  accommodate  the 
extremity  to  its  different  offices.  Is  it  not  more  pleasing 
to  see  the  reason  of  this  most  surprising  adjustment, 
than  merely  to  say  it  is  a law  ? 

There  is  yet  another  opinion,  which  will  suggest 
itself  by  the  perusal  of  the  following  chapter,  to  those 
who  have  read  the  more  modern  works  on  Natural 
History.  It  is  supposed  that  the  same  elementary 
parts  belong  to  all  animals,  and  that  the  varieties  of 
structure  are  attributable  to  the  transposition  and 
moulding  of  these  elementary  parts.  I find  it  utterly 
impossible  to  follow  up  this  system  to  the  extent  which 
its  abettors  would  persuade  us  to  be  practicable.  I 
object  to  it  as  a means  of  engaging  us  in  very  tri- 
fling pursuits, — and  of  diverting  the  mind  from  the 
truth  ; from  that  conclusion,  indeed,  to  which  I may 
avow  it  to  be  my  intention  to  carry  the  reader.  But 
this  discussion  also  must  follow  the  examples,  and 
we  shall  resume  it  in  a latter  part  of  the  volume. 


4* 


CHAPTER  III. 


THE  COMPARATIVE  ANATOMY  OF  THE  HAND. 

In  this  enquiry,  we  have  before  us  what  in  the 
strictest  sense  of  the  word  is  a system.  All  the  indi- 
viduals of  the  extensive  division  of  the  animal  king- 
dom which  we  have  to  review,  possess  a cranium  for 
the  protection  of  the  brain, — a heart,  implying  a 
peculiar  circulation, — five  distinguishable  organs  of 
sense  ; but  the  grand  peculiarity,  whence  the  term 
vertebrata  is  derived,  is  to  be  found  in  the  spine  ; that 
chain  of  bones  which  connects  the  head  and  body, 
and,  like  a keel,  serves  as  a foundation  for  the  ribs  ; 
or  as  the  basis  of  that  fabric  which  is  for  respiration. 

I have  said,  that  we  are  to  confine  ourselves  to  a 
portion  only  of  this  combined  structure  ; to  separate 
and  examine  the  anterior  extremity,  and  to  observe 
the  adaptation  of  its  parts,  through  the  whole  range 
of  these  animals.  We  shall  view  it  as  it  exists  in 
man,  and  in  the  higher  division  of  animals  which 
give  suck,  the  mammalia — in  those  which  propagate 
by  eggs,  the  oviparous  animals, — birds,  reptiles,  am- 
phibia, and  fishes;  and  we  shall  find  the  bones  which 
are  identified  by  distinct  features,  adjusted  to  various 
purposes,  in  all  the  series,  from  the  arm  to  the  fin. 
We  shall  recognize  them  in  the  mole,  formed  into  a 
powerful  apparatus  for  digging,  by  which  the  animal 
soon  covers  itself,  and  burrows  its  way  under  ground. 
In  the  wing  of  the  eagle  we  shall  count  ever}"  bone 
adapted  to  a new  element,  and  as  powerful  to  rise  in 
the  air,  as  the  fin  of  the  salmon  is  to  strike  through 
the  water.  The  solid  hoof  of  the  horse,  the  cleft 
foot  of  the  ruminant,  the  retractile  claw  of  the  feline 
tribe,  the  long  folding  nails  of  the  sloth,  are  among 


OF  THE  SHOULDER. 


43 


the  many  changes  that  are  found  in  the  adjustment 
of  the  chain  of  bones  which,  in  man,  ministers  to 
the  compound  motions  of  the  hand. 


OF  THE  SHOULDER, 


44 


COMPARATIVE  ANATOMY 


Were  it  my  purpose  to  teach  the  elements  of  this 
subject,  I should  commence  with  examining  the 
lowest  animals,  and  trace  the  bones  of  the  anterior 
extremity  as  they  come  to  resemble  the  human  arm, 
and  to  be  employed  for  a greater  variety  of  uses  in 
the  higher  animals ; but  as  my  present  object  is  illus- 
tration only,  I shall  begin  with  the  human  hand,  and 
compare  its  parts.  With  this  view,  I shall  divide 
the  extremity  into  the  shoulder,  arm,  and  hand,  and 
treat  each  subdivision  with  a reference  to  its  structure 
in  animals. 

In  viewing  the  human  figure,  or  human  skeleton, 
in  connection  with  our  present  subject,  we  remark 
the  strength  and  solidity  of  the  lower  extremities,  in 
contrast  with  the  superior.  Not  onl)^  are  the  lower 
limbs  longer  and  larger  than  those  of  any  other  ani- 
mal, but  the  pelvis  is  i\fider,  and  the  obliquit}’  of  the 
neck  of  the  thigh-bone  greater.  The  distances  of 
the  large  processes  on  the  upper  ends  of  the  thigh- 
bones (the  trochanters,)  from  the  sockets,  are  also 
greater  than  in  any  of  the  vertebrata.  Altogether 
the  strength  of  these  bones,  the  size  and  prominence 
of  their  processes,  the  great  mass  of  the  muscles  of 
the  loins  and  hips,  distinguish  man  from  every  other 
animal ; they  secure  to  him  the  upright  posture,  and 
give  him  the  perfect  freedom  of  the  arms,  for  pur- 
poses of  ingenuity  and  art. 

The  Chimpanzee*  is  an  ape  which  stands  high  in 

* Simla  troglodytes,  from  the  coast  of  Guinea,  more  human  in  its 
form,  and  more  easily  domesticated  than  the  ourang-outang.  tVe 
would  do  well  to  consider  the  abode  of  these  creatures  in  a state  of 
nature — vast  forests  extending  in  impenetrable  shade  below,  whilst 
above,  and  exposed  to  the  light,  there  is  a scene  of  verdure  and 
beauty ; this  is  the  home  of  those  monkej's  and  lemurs  which  have 
extremities  like  hands.  In  many  of  them  the  hinder  extremity  has 
the  more  perfect  resemblance  to  a hand ; in  the  Coaita  we  see  tlie 
great  toe  assuming  the  characters  of  a thumb,  whilst  in  tlie  fore  paw, 
the  thumb  is  not  distinguishable,  being  hid  in  the  skin.  In  short, 
these  paws  are  not  approximations  to  the  hand,  corresponding  tvith 
a higher  ingenuity,  but  are  adaptations  of  the  feet  to  the  branches 
on  which  the  animals  climb. 


OF  THE  SHOULDER. 


45 


tlie  order  of  quadrumana,  yet  we  cannot  mistake  his 
capacities  : that  the  lower  extremities  and  pelvis,  or 
hips,  were  never  intended  to  give  him  the  erect  pos- 
ture, or  only  for  a moment ; but,  for  swinging,  or  for 
a vigorous  pull,  who  can  deny  him  power  in  those 
long  and  sinewy  arms. 

The  full  prominent  shoulders,  and  the  consequent 
squareness  of  the  trunk,  are  equally  distinctive  of 
man,  with  the  strength  of  his  loins  ; they  indicate  a 
free  motion  of  the  hand. 


OP  THE  BONES  OF  THE  SHOULDER. 

The  bones  of  the  shoulder,  being  those  which  give 
firm  attachment  to  the  upper  extremity,  and  which 
afford  origins  to  the  muscles  of  the  arm  and  fore  arm, 
are  simple,  if  studied  in  man,  or,  indeed,  in  any  one 
genus  of  animals  ; but  considered  in  reference  to  the 
whole  of  the  vertebral  animals,  they  assume  a very 
extraordinary  degree  of  intricacy.  We  shall,  how- 
ever, find  that  they  retain  their  proper  office,  notwith- 
standing the  strange  variations  in  the  form  of  the 
neighbouring  parts.  In  man  they  are  directly  con- 
nected with  the  great  apparatus  of  respiration  ; but 
in  other  animals  Ave  shall  see  the  ribs,  as  it  were, 
withdrarvn  from  them,  and  the  bones  of  the  shoulder, 
or  fundamental  bones  of  the  extremity,  curiously  and 
mechanically  adapted  to  perforin  their  office,  without 
the  support  of  the  thorax.  We  shall  not,  horvever, 
anticipate  the  difficulties  of  this  subject,  but  look  first 
upon  that  which  is  most  familiar  and  easy,  the 
shoulder  of  man  in  comparison  with  the  varieties  in 
the  mammalia. 

The  clavicle,  or  collar  bone,  is  that  which  runs 
across  from  the  breast  bone  to  the  top  of  the  shoulder. 
The  square  form  of  the  chest,  and  the  free  exercise 
of  the  hand,  are  very  much  owing  to  this  bone.  It 
keeps  the  shoulders  apart  from  the  chest,  and  throws 


46 


COMPARATIVE  ANATOMY 


the  action  of  the  muscles  upon  the  ann  bone,  ivhich, 
but  for  it,  would  be  drawn  inwards,  and  contract  the 
upper  part  of  the  trunk. 


If  we  take  the  motions  of  the  anterior  extremity 
in  different  animals,  as  our  guide,  we  shall  see  why 
this  bone  is  perfect  in  some,  and  entirely  wanting  in 
others.  Animals  which  fly,  or  dig,  or  climb,  as  bats, 
moles,  porcupines,  squirrels,  ant-eaters,  armadilloes, 
and  sloths,  have  this  bone,  for  in  them,  a lateral  or 
outward  motion  is  required.  There  is  also  a certain 
degree  of  freedom  in  the  anterior  extremity  of  the 
cat,  dog,  martin,  and  bear  ; the)’^  strike  with  the  paw, 
and  rotate  the  wrist  more  or  less  extensively,  and 
they  have  therefore  a clavicle,  though  an  imperfect 
one.  In  some  of  these,  even  in  the  lion,  the  bone 
which  has  the  place  of  the  clavicle  is  very  imperfect 
indeed ; and  if  attached  to  the  shoulder,  it  does  not 
extend  to  the  sternum  ; it  is  concealed  in  the  flesh, 
and  is  like  the  mere  rudiments  of  the  bone.  But, 
however  imperfect,  it  marks  a correspondence  in  the 


A.  Triangular  portion  of  the  Sternum,  e.  b.  Clavicles,  c.  c. 
Scapulae,  d.  Coracoid  process  of  the  Scapula,  e.  Acromion  pro- 
cess of  the  Scapulae. 


OF  THE  SHOULDER. 


47 


bones  of  the  shoulder  to  those  of  the  arm  and  paw, 
and  the  extent  of  motion  enjoyed. 

When  the  bear  stands  up,  we  perceive,  by  his 
ungainly  attitude  and  the  motion  of  his  paws,  that 
there  must  be  a wide  difference  in  the  bones  of  his 
upper  extremity,  from  those  of  the  ruminant  or 
solipede.  He  can  take  the  keeper’s  hat  from  his 
head,  and  hold  it ; he  can  hug  an  animal  to  death. 
The  ant-bear  especially,  as  he  is  deficient  in  teeth, 
possesses  extraordinary  powers  of  hugging  with  his 
great  paws  ; and,  although  harmless  in  disposition, 
he  can  squeeze  his  enemy,  the  jaguar,  to  death. 
These  actions,  and  the  power  of  climbing,  result  from 
the  structure  of  the  shoulder,  or  from  possessing  a 
collar  bone,  however  imperfect. 

Although  the  clavicle  is  perfecti  in  man,  thereby 
corresponding  with  the  extent  and  freedom  of  the 
motion  of  his  hand,  it  is  strongest  and  longest,  com- 
paratively, in  the  animals  which  dig  or  fly,  as  in  the 
mole  and  the  bat. 

Preposterous  as  the  forms  of  the  kangaroo  appear 
to  us,  yet  even  in  this  animal  we  see  a relation  pre- 
served between  the  extremities.  He  sits  upon  his 
strong  hind  legs  and  tail,  tripod  like,  with  perfect 
security,  and  his  fore  paws  are  free.  He  has  a cla- 
vicle, and  possessing  that  bone  and  the  corresponding 
motions,  is  not  without  means  of  defence  ; for  with 
the  anterior  extremities  he  seizes  the  most  powerful 
dog,  and  then  drawing  up  his  hinder  feet,  he  digs  his 
sharp  pointed  hoofs  into  his  enemy,  and  striking  out, 
tears  him  to  pieces.  Though  possessed  of  no  great 
speed,  and  without  horns,  teeth,  or  claws,  and,  as  Ave 
should  suppose,  totally  defenceless,  nature  has  not 
been  negligent  of  his  protection.*  ^ 

* There  is  in  the  form  of  the  kangaroo,  and  especially  m its  skele- 
ton, sometliiiig  incongruous,  and  in  contrast  with  the  usual  shape  of 
quadrupeds.  The  head,  trunk,  and  fore  paws,  appear  to  be  a por- 
tion of  an  animal,  unnaturally  joined  to  another  of  greater  dimensions 
and  strength.  It  is  not  easy  to  say  what  are,  or  what  were,  the  exte- 


48 


COMPARATIVE  ANATOMY 


It  cannot  be  better  shown,  that  the  function  or 
use  of  a part,  determines  its  fonn,  than  by  looking  to 
the  clavicle  and  scapula  of  the  bird. 

Three  bones  converge  here,  to  the  shoulder  joint, 
the  furculum,  clavicle,  and  scapula  ; but  none  of 
these  have  the  resemblance  which  their  names  would 
imply.  The  scapula  is  the  long  thin  bone,  like  the 
blade  of  a knife ; and  the  clavicle  is  that  stronger 
portion  of  bone  which  is  articulated  with  the  breast 
bone  ; this  leaves  the  furculum  as  a new  part.  Now 
I think,  tliat  the  furculum,  or  fork  bone,  which  in 
carving,  we  detach,  after  removing  the  wings  of  a 
fowl,  corresponds  with  the  form  and  place  of  the 
clavicle  ; and  if  we  so  consider  it,  we  ma)'^  then  take 


rior  relations  corresponding  with  tlie  very  peculiar  form  of  this 
animat ; but  the  interior  anatomy  is  accommodated,  in  a most  remark- 
able manner,  to  the  enormous  hinder  extremities. 

The  uterine  system  of  the  female  is  diminutive,  and  does  not  under- 
go the  developement,  which  universally  takes  place  in  other  animals. 
The  young,  instead  of  remaining  within  the  mother  for  the  period  of 
gestation,  become,  by  some  extraordinary  mode  of  expulsion,  attached 
to  the  teats  ; where  they  hang  by  the  mouth,  covered  by  an  exterior 
pouch,  until,  from  minute  and  shapeless  things,  they  are  matured  to 
the  degree  in  which  the  young  of  other  animals  are  usually  produced. 
The  artery  which  supphes  the  milk  glands,  is  the  epigastric,  a branch 
of  the  great  artery  of  the  thigh  ; juid  in  this  curious  manner  is  tlie 
provision  for  the  young  drawn  from  the  great  limbs  of  the  mother, — 
certainly  the  part  best  enabled  to  supply  it. 

I think  I perceive  the  reason  of  this  very  peculiar  manner  ofbring- 
ing  forth  the  young,  to  be  in  the  form  of  the  animal  and  its  upright 
position.  The  argument  would  stand  thus,  were  we  here  at  liberty 
to  discuss  it : 1.  An  upright  position  of  the  mother  requires  a pelvis 
of  a peculiar  and  comple.x  construction.  2.  A pelvis,  of  tliis  construc- 
tion, requires  that  the  form  of  the  offspring  shall  accurately  corres- 
pond, and  that  the  anterior  part  of  the  foetus  shall  much  exceed  in 
size  the  posterior  parts.  3.  But  the  kangaroo  is,  in  shape,  the  veiy 
reverse, — the  head  could  not,  consistently  tiuth  the  conformation  of 
the  whole  animal,  be  larger  than  the  hips  and  liinder  extremities.  4. 
Nature  has  accomplished  her  work  safely,  and  by  tlie  simplest 
means,  by  anticipating  the  period  of  the  separation  of  the  foetus,  and 
providing  for  the  growth  of  the  oftspring,  exterior  to  the  cirde  of 
bones  through  which  its  birth  must  take  place.  It  will,  perhaps,  be 
objected  to  this  reasoning,  tliat  the  order  diddphis  (witli  a double 
womb)  embraces  animals  which  have  no  such  remaikable  dispro- 
portion in  the  hinder  extremities. 


OF  THE  SHOULDER. 


49 


the  strong  bone,  commonly  called  the  clavicle,  as  a 
process  of  the  irregularly  formed  scapula.  However 
this  may  be,  what  we  have  to  admire  in  birds,  is  the 
mode  in  which  the  bones  are  fashioned,  to  strength- 
en the  articulation  of  the  shoulder,  and  to  give  extent 
of  surface  for  the  attachment  of  muscles. 

Another  peculiarity  in  birds  is,  that  there  is  not  an 
alternate  motion  of  the  wings  ; their  extremities,  as 
we  may  continue  to  call  them,  move  together  in  fly- 
ing ; and,  therefore,  the  clavicles  are  joined,  forming 
the  furculum. 


OF  THE  SCAPULA. 

If  we  attend  to  the  scapula,  or  shoulder-blade,  we 
shall  better  understand  the  influence  of  the  bones  of 
the  shoulder,  on  the  motions  and  speed  of  animals. 
The  scapula  is  that  flat  triangular  bone,  which  lying 
on  the  ribs,  and  cushioned  with  muscles,  shifts  and 
revolves  with  each  movement  of  the  arm.  The 
muscles  converge  from  all  sides  towards  it,  from  the 
head,  spine,  ribs,  and  breast  bone.  These  acting  in 
succession,  roll  the  scapula  and  toss  the  arm,  in  every 
direction.  When  the  muscles  combine  in  action, 
they  fix  the  bone,  and  either  raise  the  ribs  in  drawing 
breath,  or  give  firmness  to  the  whole  frame  of  the  trunk. 

Before  I remark  further  on  the  influence  of  the 
scapulae  on  the  motions  of  the  arm,  I shall  g've  an 
instance  in  proof  of  a very  important  function  which 
they  perform.  Hearing  that  there  was  a lad  of  four- 
teen years  of  age,  born  without  arms,  I sent  for  him. 
I found  that  indeed  he  had  no  arms,  but  he  had  cla- 
vicles and  scapulae.  When  I made  this  boy  draw  his 
breath,  the  shoulders  were  raised,  that  is  to  say,  the 
scapulae  were  drawn  up,  were  fixed,  and  became  the 
points  from  which  the  broad  muscles  of  the  chest 
diverged  towards  the  ribs,  to  draw  and  expand  them 
in  respiration.  We  would  do  well  to  remember  this 
double  office  of  the  scapula  and  its  muscles,  that 

5 


50 


ANATOMY  OF  THE 


whilst  it  is  the  very  foundation  of  the  bones  of  the 
upper  extremity,  and  never  wanting  in  any  animal 
that  has  the  most  remote  resemblance  to  an  arm,  it 
is  the  centre  and  point  d’appui  of  the  muscles  of 
respiration,  and  acts  in  that  capacity,  where  there 
are  no  extremities  at  all ! 

We  perceive,  that  it  is  only  in  certain  classes  of  ani- 
mals, that  the  scapula  is  joined  to  the  trunk  by  bone, 
that  is,  through  the  medium  of  a clavicle  ; and  a 
slight  depression  on  a process  of  the  scapula,  when 
discovered  in  a fossil  state,  will  declare  to  the  geolo- 
gist, the  class  to  which  the  animal  belonged.  For 
example,  there  are  brought  over  to  this  country  the 
bones  of  the  Megatherium,  an  animal,  which  must 
have  been  as  large  as  the  elephant ; of  the  anterior 
extremity  there  is  only  the  scapula  ; and  on  the  ex- 
tremity of  the  process,  which  is  called  acromion, 
of  that  bone,  there  is  a mark  of  the  attachment  of  a 
clavicle.  This  points  out  the  whole  constitution  of 
the  extremity,  and  that  it  enjoyed  perfect  freedom  of 
motion.  Other  circumstances  will  declare  whether 
that  extensive  motion  was  bestowed,  so  that  the 
animal  might  dig  with  its  huge  claws  like  some  of 
the  edentata,  or  strike  like  the  feline  tribe. 

Some  interest  is  attached  to  the  position  of  the 
scapula,  in  the  horse.  In  him,  and  in  other  quadru- 
peds, with  the  exceptions  which  I have  made,  there 
is  no  clavicle,  and  the  connection  between  the  ex- 
tremity and  the  trunk,  is  solely  through  muscles. 
That  muscle,  called  serratus  inagnus,  which  is  a 
large  one  in  man,  is  particularly  powerful  in  the 
horse  ; for  the  weight  of  the  trunk  hangs  upon  this 
muscle.  In  the  horse,  as  in  most  quadrupeds,  the 
speed  results  from  the  strength  of  the  loins  and 
hinder  extremities,  for  it  is  the  muscles  there  which 
propel  the  animal.  But  were  the  anterior  extremi- 
ties joined  to  the  trunk  firmly,  and  by  bone,  thej- 
could  not  withstand  the  shock  from  the  descent 
of  the  whole  weight  thro^^m  forwards ; even  though 


horse’s  shoulder. 


51 


they  were  as  powerful  as  the  posterior  extremities, 
they  would  sufi’er  fracture  or  dislocation.  We  can- 
not but  admire,  therefore,  the  provision  in  all  quad- 
rupeds whose  speed  is  great,  and  whose  spring  is 
extensive,  that,  from  the  structure  of  their  bones, 
they  have  an  elastic  resistance,  by  which  the  shock 
of  descending  is  diminished. 

If  we  observe  the  bones  of  the  anterior  extremity 
of  the  horse,  we  shall  see  that  the  scapula  is  oblique 
to  the  chest ; the  humerus,  oblique  to  the  scapula  ; 
and  the  bones  of  the  fore  arm  at  an  angle  with  the 
humerus.  Were  these  bones  connected  together  in 
a straight  line,  end  to  end,  the  shock  of  alighting 
woidd  be  conveyed  through  a solid  column,  and  the 
bones  of  the  foot,  or  the  joints,  would  suffer  from  the 
concussion.  When  the  rider  is  thrown  forwards  on 
his  hands,  and  more  certainly  when  he  is  pitched  on 
his  shoulder,  the  collar  bone  is  broken,  because  in 
man,  this  bone  forms  a link  of  connection  betAveeu 
the  shoulder  and  the  trunk,  so  as  to  receive  the 
Avhole  shock  ; and  the  same  would  happen  in  the 
horse,  the  stag,  and  all  quadrupeds  of  great  strength 
and  swiftness,  were  not  the  scapulae  sustained  by 
muscles,  and  not  by  bone,  and  did  not  the  bones 
recoil  and  fold  up. 

The  horse-jockey  runs  his  hand  down  the  horse’s 
neck,  in  a knowing  way,  and  says,  “ this  horse  has 
got  a heavy  shoulder,  he  is  a slow  horse  !”  He  is 
right,  but  he  does  not  understand  the  matter ; it  is 
not  possible  that  the  shoulder  can  be  too  much  loaded 
with  muscle,  for  muscle  is  the  source  of  motion,  and 
bestows  power.  What  the  jockey  feels,  and  forms 
his  judgment  on,  is  the  abrupt  transition  from  the 
neck  to  the  shoulder,  which,  in  a horse  for  the  turf, 
ought  to  be  a smooth  undulating  surface.  This  ab- 
ruptness, or  prominence  of  the  shoulder,  is  a conse- 
quence of  the  upright  position  of  the  scapula  ; the 
sloping  and  light  shoidder  results  from  its  obliquit}'. 
An  upright  shoulder  is  the  mark  of  a stumbling 


52 


ANATOMY  OF  THE 


horse  ; it  does  not  revolve  easil}?^,  to  throw  forward 
the  foot. 

Much  of  the  strength,  if  not  the  freedom  and  rapi- 
dity of  motion,  of  a limb,  will  depend  on  the  angle 
at  which  the  bones  lie  to  each  other  ; for,  this  mainly 
affects  the  insertion,  and,  consequently,  the  power  of 
the  muscles.  We  know,  and  may  every  moment 
feel,  tha.t  when  the  arm  is  extended,  we  possess  Uttle 


A.  Scapula.  E.  Humerus,  y.  Tuberosity  of  the  Huraems.  c 
Olecranon,  or  projection  of  the  Ulna.  d.  Radius. 


horse’s  shoulder. 


53 


power  in  bending  it ; but  as  we  bend  it  the  power  is 
increased  ; which  is  owing  to  the  change  in  the  direc- 
tion of  the  force  acting  upon  the  bone ; or,  in  other 
words,  because  the  tendon  becomes  more  perpendi- 
cular to  the  lever.  A scapula  which  inclines  ob- 
liquely backwards,  increases  the  angle  at  which  it 
lies  with  the  humerus,  and,  consequently,  improves 
the  effect  of  those  muscles  which  pass  from  it  to  the 
humerus.  We  have  only  to  turn  to  the  skeleton  of 
the  elephant,  the  ox,  the  elk,  or  the  stag,  to  see  the 
confirmation  of  this  principle.  When  the  scapula  is 
oblique,  the  serratus  muscle,  which  passes  from  the 
ribs  to  its  uppermost  part,  has  more  power  in  rolling 
it.  When  it  lies  at  right  angles  with  the  humerus, 
the  muscles  which  are  attached  to  the  latter,  (at  B.) 
act  with  more  effect.  And  on  the  same  principle,  by 
the  oblique  position  of  the  humerus,  and,  conse- 
quently, its  obliquity  in  reference  to  the  radius  and 
ulna,  the  power  of  the  muscle  inserted  (at  C.)  into 
the  olecranon,  is  increased.  On  the  whole,  both 
power  and  elasticity  are  gained  by  this  position  of  the 
superior  bones  of  the  fore-leg.  It  gives  to  the  ani- 
mal that  springs,  a larger  stretch  in  throwing  himself 
forwards,  and  security,  in  a soft  descent  of  his  weight. 
A man,  standing  upright,  cannot  leap  or  start  off  at 
once  ; he  must  first  sink  down,  and  bring  the  bones 
of  his  extremities  to  an  angle.  But  the  antelope,  or 
other  timid  animals  of  the  class,  can  leap  at  once,  or 
start  off  in  their  course  without  preparation  : another 
advantage  of  the  oblique  position  of  their  bones  when 
at  rest. 

The  leg  of  the  elephant  is  obviously  built  for  the 
purpose  of  sustaining  the  huge  bulk  of  the  animal, 
whilst  in  the  camel  we  have  a perfect  contrast. 

Were  we  to  compare  the  bones  of  these  larger 
animals  with  any  form  of  architecture,  we  might 
say,  it  was  the  Egyptian,  or  rather  like  the  Cyclo- 
pean walls  of  some  ancient  city  ; they  are  huge  and 
shapeless,  and  piled  over  each  other,  as  if  they  were 


54 


COMPARISON  OF  THE  BONES 


destined  more  to  sustain  the  weight,  than  to  permit 
motion. 

We  further  perceive,  from  the  comparison  of  these 
sketches,  that  if  the  humerus  be  placed  obliquely,  it 
must  necessarily  be  short,  otherwise  it  would  throw 
the  leg  too  far  back,  and  make  the  head  and  neck 
project.  It  is  one  of  the  “ points”  of  a horse  to  have 
the  humerus  short.  And  not  only  have  all  animals  of 
speed  this  character,  but  birds  of  long  flight,  as  the 
swallow,  have  short  humeri.  This  is  owing,  I think, 
to  another  circumstance,  that  in  the  wing,  the  short 
humerus  causes  a quicker  extension ; for  the  further 
extremity  of  the  bone  moving  in  a lesser  circle, 
makes  the  gyi'ation  be  more  rapid. 

If  we  take  the  bones  of  the  shoulder  as  a distinct 
subject,  and  trace  them  comparative!)',  we  shall  be 
led  to  notice  some  very  cmious  modifications  in 
them.  We  have  already  seen  that  there  are  two 
objects  to  be  attained  in  the  construction  of  these 
bones.  In  man,  and  mammalia,  they  constitute  an 
important  part  of  the  organ  of  respiration  ; and  they 
conform  to  the  structure  of  the  thorax.  But  we 
shall  find  that  in  some  animals,  this  function  is  in  a 
manner  w'ithdrawn  from  them  ; the  scapulae  and  the 
clavicles  are  left  without  the  support  of  the  ribs. — 
These  bones  forming  the  shoulder,  therefore,  require 
additional  carpentry  ; or  they  must  be  laid  together 
on  a new  principle.  In  the  batrachian  order,  for 
example  in  the  frog,  the  tliorax,  as  constituted  of 
ribs,  has  disappeared ; the  mechanism  of  respiration 
is  altogether  different  from  what  it  is  in  the  mamma- 
lia. Accordingly,  we  find  that  the  bones  of  the 
shoulder  are  on  a new  model ; they  form  a broad 
and  flat  circle,  sufficient  to  give  secure  attachment  to 
the  extremity,  and  affording  a large  space  for  the 
lodgment  of  the  muscles  which  move  the  arm. — 
Perhaps  the  best  example  of  this  structure  is  in  the 
siren  and  proteus;  where  the  ribs  are  reduced  to  a 
very  few^  imperfect  processes,  attached  to  the  ante- 


OP  THE  ELEPHANT  AND  CAMEL. 


55 


rior  dorsal  vertebras ; and  where  the  bones  of  the 
extremity,  being  deprived  of  all  sup}X)it  from  the 
thorax,  depend  upon  themselves  for  security.  Here 
the  bones,  corresponding  to  the  sternum,  clavicles, 
and  scapulae,  are  found  clinging  to  the  spine,  and 
forming,  like  the  pelvis,  a circle,  to  the  lateral  part 
of  which  the  humerus  is  articulated. 

In  the  chelonian  order,  the  tortoises,  we  see  another 
design  accomplished,  in  the  union  of  these  bones ; 
and  the  change  is  owing  to  a very  curious  circum- 
stance. The  spine  and  ribs  of  these  animals  fonn 
the  rafters  of  their  strong  shell ; and  consequently 
they  are  external  to  the  bones  of  the  shoulder.  The 
scapulae  and  clavicles  being  thus  within  the  thorax, 
and  having  nothing  in  their  grasp,  neither  ribs  nor 
spine,  they  must  necessarily  fall  together,  and  form 
a circle,  in  order  to  afford  a fixed  point  to  which  the 
extremity  may  be  attached.  It  would,  indeed,  be 


A.  Scapula.  B.  Acromion  process,  c.  Coracoid  bone.  D.  Glenoid 
cavity. 


I 


56 


COMPARATIVE  ANATOMY 


strange  if,  now  being  joined  for  the  purpose  of  giving 
attachment  to  the  humerus,  and  in  circumstances, 
as  we  may  express  it,  so  very  new,  they  preserved 
any  resemblance  to  the  forms  which  we  have  been 
contemplating  in  the  higher  animals.  In  the  figure  on 
the  preceding  page,  we  have  the  bones  of  the  shoul- 
der of  the  turtle ; and  it  is  readily  perceived  how  much 
they  have  changed  both  their  shape  and  their  offices. 
That  part  which  is  most  like  a scapula  in  shape,  lies  on 
the  fore  part,  instead  of  the  back  part ; and  the  bones 
which  hold  the  shoulders  apart,  abut  upon  the  spine, 
instead  of  upon  the  sternum.  Hence  it  appears  idle 
to  follow  out  these  bones  under  the  old  denominations, 
or  such  as  are  applicable  to  their  condition  in  the 
higher  animals. 

In  fishes,  where  the  apparatus  of  respiration  has 
undergone  another  entire  change,  and  where  there 
are  no  proper  ribs,  the  bones  which  give  attachment 
to  the  pectoral  fin,  are  still  called  the  bones  of  the 
shoulder  ; and  that  which  is  named  scapular  appen- 
dage, is,  in  fact,  attached  to  the  bones  of  the  head. 
So  that  the  whole  consists  of  a circle  of  bones,  which, 
we  ma)^  say,  seek  security  of  attachment  by  approach- 
ing the  more  solid  part  of  the  head,  in  defect  of  a 
firm  foundation  in  the  thorax. 

Thus,  the  bones  which,  in  a manner,  give  a foun- 
dation to  those  of  the  anterior  extremity,  have  been 
submitted  to  a new  modelling,  in  correspondence  with 
every  variety  in  the  apparatus  of  respiration ; and 
they  have  yet  maintained  their  pristine  office. 

The  naturalist  will  not  be  surprised,  on  finding  an 
extraordinary  intricacy  in  the  shoulder  apparatus  of 
the  ornithorynchus  paradoxus,  since  tlje  whole  frame 
and  organs  of  this  animal  imply,  that  it  is  intermediate 
between  mammalia  and  birds ; and  it  is  placed  in  the 
list  of  edentata.  We  introduce  it  here,  as  another 
instance  of  the  changes  wliich  the  bones  of  the 
shoulder  undergo  with  every  new  office,  and  in  cor- 
respondence with  the  motions,  of  the  extiemity; 


OF  THE  BONES  OF  THE  SHOULDER. 


57 


whether  it  be  to  support  the  weight  in  mnning,  or  to 
give  freedom  to  the  arm,  or  to  provide  for  flying,  or 


for  performing  equally  the  act  of  creeping  and  of 
swimming. 

Unprofitable  as  the  enquiry  may  seem,  there  is  no 
other  way  by  which  the  geologist  can  distinguish  the 
genera  of  those  oviparous  reptiles,  which  he  finds 
imbedded  in  the  secondary  strata,  than  by  studying 
the  minute  processes  and  varying  characters  of  these 
bones,  in  the  different  classes  of  animals.  In  the 
ichthyosaurus,  and  plesiosaurus,  the  inhabitants  of  a 
former  world,  and  now  extinct,  we  perceive  a consid- 
erable deviation  from  the  perfection  of  the  bones  of  the 
arm  and  hand,  compared  with  the  frog  and  tortoise : 
but  if  strength  is  the  object,  there  is  a greater  degree 
of  perfection  in  the  bones  of  the  shoulder.  The  expla- 
nation of  this  is,  that  the  ribs  and  sterno-costal  arch- 
es, constituting  the  thorax  are  more  perfect,  than  in 


A.  Clavicle,  b.  Coracoid  bone.  c.  A new  bone,  introduced  into 
the  apparatus,  which  articulates  with  the  coracoid  bone,  and  lies 
interior  to  the  clavicle,  d.  Scapula,  e.  Acromion  Scapul®. 


58 


COMPARATIVE  ANATOMY 


the  chelonian  and  batrachian  orders  ; and  the  bones 
of  the  shoulder  are  therefore  external,  and  resemble 
those  of  the  crocodile  ; yet  the  ribs  are  so  weak  as  to 
be  incapable  of  sustaining  the  pow’erful  action  of  the 
anterior  extremities ; accordingly,  the  bones,  which 
by  a kind  of  licence  we  continue  to  call  clavicle, 
omoplate  or  scapula,  and  coracoid,  though  strangely 
deviating  from  the  original  form  and  connections, 
constitute  a texture  of  considerable  strength,  which 
perfects  the  anterior  part  of  the  trunk,  and  gives 
attachment  and  lodgment  to  the  powerful  muscles  of 
the  paddle. 

But  in  giving  their  attention  to  this  subject,  it  does 
not  appear  that  naturalists  have  hit  upon  the  right 
explanation  of  the  peculiar  structure,  and  curious 
varieties  of  these  bones.  Why  is  the  apparatus  of 
respiration  so  totally  changed  in  these  classes  of  ani- 
mals 1 They  are  cold  blooded  animals  ; they  require 
to  respire  less  frequently  than  other  creatures,  and 
they  remain  long  under  water.  I conceive  that  the 
peculiarity  in  their  mode  of  respiration  corresponds 
with  this  property.  Hence  their  vesicular  lungs, 
their  mode  of  swallowing  the  air,  instead  of  inhalmg 
it ; and  hence,  especially,  their  power  of  compressing 
the  body  and  expelling  the  air ; it  is  this,  I imagine, 
which  enables  them  to  go  under  the  water  and  crawl 
upon  the  bottom  ; without  this,  that  is  to  say,  had  they 
possessed  the  lungs  of  warm  blooded  annuals,  which 
are  compressible  only  in  a slight  degree,  their  capa- 
city of  remaining  under  water  would  have  left  them 
struggling  against  their  buoyancy,  like  a man  or 
any  of  the  mammalia  when  diving.  The  girdle  of 
bones  of  the  shoulder  is  constituted  with  a certain 
regard  to  the  peculiar  action  of  respiration,  and  to 
the  pliancy  of  the  body,  in  order  that  the  vesicular 
lungs  may  be  compressed,  and  the  specific  weight 
diminished.  The  facility  which  the  absence  of  ribs 
gives,  in  the  batrachian  order,  and  the  extreme 
wealcness  and  pliancy  of  these  bones  in  the  saurians, 


OF  THE  HUMERUS. 


59 


for  admitting  the  compression  of  the  lungs  extended 
through  the  abdomen,  must  be,  as  I apprehend,  pecu- 
liarities adapted  to  the  same  end. 


OF  THE  HUMERUS. 

The  demonstration  of  this  bone  need  not  be  so  dry 
a matter  of  detail  as  the  anatomist  makes  it.  We 
may  see  in  it  that  curious  relation  of  parts  which  has 
been  so  successfully  employed  by  Paley  to  prove  de- 
sign, and  from  which  the  genius  of  Baron  Cuvier  has 
brought  out  some  of  the  finest  examples  of  inductive 
reasoning. 

In  looking  to  the  head  of  this  bone  in  the  human 
skeleton,  (see  the  fig.  page  43,)  we  observe  the  great 
hemispherical  surface  for  articulation  with  the  gle- 
noid cavity  of  the  scapula,  and  we  see  that  the  two 
trrbercles,  near  the  joint,  are  depressed,  and  do  not 
interfere  with  the  revolving  of  the  humerus,  by  strik- 
ing against  the  scapula. 

Such  appearances  alone  are  sufficient  to  show  that 
all  the  motions  of  the  arm  are  free.  To  give  assur- 
ance of  this,  suppose  that  the  geologist  has  picked 
up  this  bone  in  interesting  circumstances.  To  what 
animal  does  it  belong  1 The  circular  form  of  the 
articulating  surface,  and  the  very  slight  projection  of 
the  tubercles,  evince  a latitude  and  extent  of  motion. 
Now,  freedom  of  motion  in  the  shoulder,  implies 
freedom  also  in  the  extremity  or  paw,  and  rotation 
of  the  bones  of  the  wrist.  Accordingly,  we  direct 
the  eye  to  that  part  of  this  humerus  which  gives 
origin  to  the  muscles  for  turning  the  wrist,  (the  S\t- 
pinator  muscles),  and  in  the  prominence  and  length  of 
the  ridge  or  crest  which  is  on  the  lower  and  outer 
side  of  the  bone,  we  have  proof  of  the  free  motion 
of  the  paw. 

Therefore,  on  finding  the  humerus  thus  character- 
ized, we  conclude,  that  it  belonged  to  an  animal  with 


60 


COMPARATIVE  ANATOMY 


sharp  moveable  claws  ; that,  in  all  probability,  it  is 
the  remains  of  a bear. 

But,  suppose  that  the  bone  found  has  a different 
character  : — That  the  tubercles  project,  so  as  to  limit 
the  motion  to  one  direction,  and  that  the  articulating 
surface  is  less  regularly  convex.  On  inspecting  the 
lower  extremity  of  such  a bone,  we  shall  perceive 
provisions  for  a deeper  and  more  secure  hinge -joint 
at  the  elbow  ; and  neither  in  the  form  of  the  articu- 
lating surface,  (which  is  here  called  trochlea),  nor  in 
the  spine  on  the  outside,  above  noticed,  will  there  be 
signs  of  the  rotation  of  one  bone  of  the  fore  arm  on 
the  other.  We  have,  therefore,  got  the  bone  of  an 
herbivorous  quadruped,  either  with  a solid  or  with  a 
cloven  foot. 

In  the  bat  and  mole  we  have,  perhaps,  the  best 
examples  of  the  moulding  of  the  bones  of  the  extre- 
iuit}q  to  correspond  with  the  condition  of  the  animal. 
The  mole  is  an  animal  fitted  to  plough  its  way  under 
ground.  In  the  bat,  the  same  system  of  bones  is 
adapted  to  form  a wing,  to  raise  the  animal  in  the 
atmosphere ; and  with  a provision  to  cling  to  the 
wall,  not  to  bear  upon.  We  recognize  in  both,  every 
bone  of  the  upper  extremitj-,  but  how  very  diflerently 
formed  and  joined  ! In  the  mole,  the  sternum  or 
breast  bone,  and  the  clavicle  are  remarkably  large  : 
the  scapula  assumes  the  form  of  a high  lever : the 
humerus  is  thick  and  short,  and  has  such  spines  for 
tire  attachment  of  muscles,  as  indicate  great  power. 
The  spines,  which  give  origin  to  the  muscles  of  rota- 
tion. project  in  an  extraordinary  mamier  ; and  the 
hand  is  large,  flat,  and  so  turned,  that  it  may  shove 
the  earth  aside  like  a ploughshare.*' 

* The  snout  may  vary  in  its  internal  structure  witlr  new  offices. 
ICaturalists  say  tliat  there  is  a new  “ element’’  in  the  pig’s  nose.  It 
has,  in  fact,  two  bones  which  admit  of  motion,  whilst  they  give  more 
strength.  Moles  have  those  bones  also,  as  tliey  plough  the  earth  with 
their  snouts.  We  have  noticed  the  manner  in  which  they  use 
their  strong  harrds  ; we  should  add  tliat  their  head  is  a wedge,  to 


OF  THE  MOLE  AND  THE  BAT 


61 


There  can  be  no  greater  contrast  to  these  bones 
than  is  presented  in  the  skeleton  of  the  bat.  In 


which  their  hands  are  assisting,  in  throwing  aside  the  earth.  The 
conformation  of  the  head  in  shape  and  strength  of  bones,  and  the 
new  adjustment  of  a muscle,  which  is  cutaneous  in  other  animals 
(the  Platisma  Myoides)  to  the  motions  of  the  head,  are  among  the 
most  curious  changes  of  common  parts  to  new  offices. 

6 


62 


ANT-EATER. 


that  animal  the  bones  are  light  and  delicate ; and 
whilst  they  are  all  marvellously  extended,  the  pha- 
langes of  the  fingers  are  elongated,  so  as  hardly  to  be 
recognized,  obviously  for  the  purpose  of  sustaining  a 
membraneous  web,  and  to  form  a wing. 

Contemplating  this  extraordinary  application  of 
the  bones  of  the  extremity,  and  comparing  them 
with  those  in  the  whig  of  a bird,  we  might  say,  that 
this  is  an  awkward  attempt — a failure.  But  before 
giving  expression  to  such  an  opinion,  we  must  un- 
derstand the  objects  required  in  this  construction. — 
It  is  not  a wing  intended  merely  for  flight,  but  one 
which,  while  it  raises  the  animal,  is  capable  of  re- 
ceiving a new  sensation,  or  sensations  in  that  exqui- 
site degree,  so  as  almost  to  constitute  a new  sense. 
On  the  fine  web  of  the  bat’s  wing,  nerves  are  distri- 
buted, which  enable  it  to  avoid  objects  in  its  flight, 
during  the  obscurity  of  night,  when  both  eyes  and 
ears^ail.  Could  the  wing  of  a bird,  covered  with 
feathers,  do  this  1 Here  then  we  have  another  ex- 
ample of  the  necessity  of  taking  every  circumstance 
into  consideration  before  we  presume  to  criticise  the 
ways  of  nature.  It  is  a lesson  of  humility.* 

In  the  next  page  we  have  a sketch  of  the  ann 
bones  of  the  Ant-eater,f  to  shew  once  more  tire  corres- 
pondence in  the  whole  extremity.  We  observe  these 
extraordinary  spines  of  the  humerus  marking  the 
power  of  the  muscles  which  are  attached  to  it ; for 
as  I have  said  before,  whether  we  examine  the  hu- 
man body,  or  the  comparative  forms  of  the  bones, 
the  distinctness  of  the  spines  and  processes  declares 
the  strength  of  the  muscles.  It  is  particularly  pleas- 

♦ Besides  the  adaptation  of  the  bat  for  flight,  through  a new  ad- 
justment of  the  bones  of  the  arm,  this  animal  has  cells  under  its  skin ; 
but  I know  not  how  far  I am  authorized  to  say  that  they  are  analo- 
gous to  the  air-cells  of  birds,  or  that  they  are  for  the  purpose  of  mak- 
ing die  bat  specifically  lighter.  They  extend  over  the  breast,  and 
under  tlie  axillae  in  some  bats  ; and  they  are  Allied  by  an  orifice  which 
communicates  with  the  pharynx. 

t Tamajidua,  from  South  America. 


ANT-EATER. 


63 


ing  to  notice  here  the  correspondence  between  the 
humerus  and  the  other  bones,  the  scapula  large  and 
with  a double  spine,  and  with  great  processes:  the  ulna 
projecting  at  the  olecranon,  and  the  radius  freely 
rotating : but  above  all,  in  the  developement  of  one 
grand  metacarpal  bone,  which  gives  attachment  to  a 
strong  claw,  we  see  a very  distinct  provision  for 
scratching  and  turning  aside  the  ant-hill.  The  whole 


64 


STRUCTURE  OF  BIRDS. 


is  an  example  of  the  relation  of  the  particular  parts 
of  the  skeleton  to  one  another  ; and  were  it  our  busi- 
ness, it  would  be  easy  to  shew,  that  as  there  is  a cor- 
respondence among  the  bones  of  the  arm,  so  is  there 
a more  universal  relation  between  those  of  the  whole 
skeleton.  As  the  structure  of  the  bones  declares  the 
provision  of  the  extremit}^  for  digging  into  the  ant- 
hills, so  we  shall  not  be  disappointed  in  our  expecta- 
tion  of  finding  a projecting  muzzle  unarmed  with 
teeth,  and  a long  tongue  provided  with  a glutinous 
secretion,  to  lick  up  the  emmets  which  are  disturbed 
by  the  animal’s  scratching. 

In  the  skeleton  of  the  cape-mole,  we  may  see,  from 
the  projecting  acromion  scapulae,  and  a remarkable  • 
process  of  the  humerus,  that  there  is  a provision  for 
the  rotation  of  the  arm,  which  implies  burrowing. 
But  the  apparatus  seems  by  no  means  so  perfect  as  in 
the  mole,  implying  that  it  digs  in  a softer  soil  than 
that  animal,  whilst  the  possession  of  gnawing  teeth 
indicates  that  it  lives  on  roots. 

In  Birds  there  is  altogether  a new  condition  of 
parts,  as  there  is  a new  element  to  contend  with. 
The  very  peculiar  form  and  structure  of  their  skele- 
ton may  be  thus  accounted  for.  First,  it  is  necessary 
that  birds,  as  they  are  buoyed  in  the  air,  be  specifi- 
cally lighter.  Secondh",  the  cuxumference  of  their 
thorax  must  be  extended,  and  the  motions  of  their 
ribs  limited,  that  the  muscles  of  the  wings  maj’  have 
sufficient  space  and  firmness  for  their  attachment. 
Both  these  objects  are  attained  by  a modification  of 
tlie  apparatus  of  breathing.  The  lungs  are  highh* 
vascular  and  spongy,  but  tliey  are  not  distended  with 
air.  The  air  is  drawn  through  their  substance  into 
the  large  cavity  common  to  the  chest  and  abdomen  ; 
and  whilst  the  great  office  of  decarbonization  of  the 
blood  is  securely  performed,  advantage  is  taken  to  let 
the  air  into  all  the  cavities,  even  into  those  of  the 
bones.  From  what  was  said  in  the  introductory 
chapter,  of  the  weight  of  the  body  being  a necessary 


STRUCTURE  OF  BIRDS. 


65 


concomitant  of  muscular  strength,  we  see  why  birds, 
by  reason  of  their  lightness,  as  well  as  by  the  confor- 
mation of  their  skeleton,  walk  badly.  And,  on  the 
other  hand,  in  observing  how  this  lightness  is  adapt- 
ed for  flight,  it  is  remarkable  how  small  an  addition 
to  their  body  will  prevent  them  rising  on  the  wing. 
If  the  griffon-vulture  be  frightened  after  his  repast,  he 
must  disgorge,  before  he  flies  ; and  the  condor,  in  the 
same  circumstances,  is  taken  by  the  Indians,  like  a 
quadruped,  by  throwing  the  lasso  over  it.* 

As  every  one  must  have  observed,  the  breast-bone 
of  birds  extends  the  whole  length  of  the  body  ; and 
owing  to  this  extension,  a lesser  degree  of  motion 
suffices  to  respiration.  So  that  a greater  surface, 
necessary  for  the  lodgement  and  attachment  of  the 
muscles  of  the  wings,  is  obtained,  whilst  that  surface 
is  less  disturbed  by  the  action  of  breathing,  and  is 
more  steady.  Another  peculiarity  of  the  skeleton  of 
the  bird  is  the  consolidation  of  the  vertebrae  of  the 
back  ; a proof,  if  any  were  now  necessary,  that  the 
whole  system  of  bones  conforms  to  that  of  the  extrem- 
ities, the  firmer  texture  of  the  bones  of  the  trunk, 
being  a part  of  the  provision  for  the  attachment  of  the 
muscles  of  the  wings. f 

The  vertebrae  of  the  back  being  fixed  in  birds,  and 
the  pelvis  reaching  high,  there  is  no  motion  in  the 
body  ; indeed,  if  there  were,  it  would  be  interrupted 
by  the  sternum.  W e cannot  but  admire,  therefore, 
the  composition  of  the  neck  and  head,  and  how  the 
extension  of  the  vertebrae,  and  the  length  and  plia- 
bility of  the  neck,  whilst  they  give  to  the  bill  the 
office  of  a hand,  become  a substitution  for  the  loss  of 

* It  is  interesting  to  notice  the  relations  of  great  functions  in  the 
animal  economy.  Birds  are  oviparous,  because  they  never  could 
have  risen  on  the  wing  had  they  been  viviparous  ; if  the  full  stomach 
of  a carnivorous  bird  retard  its  flight,  we  perceive  that  it  could  not 
have  carried  its  young.  The  light  body,  the  quill-feathers,  Ore  bill, 
and  the  laying  of  eggs,  are  all  necessarily  connected. 

f The  ostrich  and  cassowary,  which  are  rather  runners  than  fliers, 
have  the  spine  loose. 


6* 


66 


STRUCTURE  adapted 


motion  in  the  bod}',  by  balancing  the  whole,  as  in 
standing,  running,  or  flying.  Is  it  not  curious  to 
observe  how  the  whole  skeleton  is  adapted  to  tins 
one  object,  the  power  of  the  wings. 

Whilst  the  ostrich  has  no  keel  in  its  breast-bone, 
birds  of  passage  are,  on  dissection,  recognisable  by 
the  depth  of  this  ridge  of  the  sternum.  The  reason  is 
that  the  angle,  formed  by  this  process  and  the  body  of 
the  bone,  affords  lodgement  for  the  pectoral  muscle, 
the  powerful  muscle  of  the  wing.  In  this  sketch  of 
the  dissection  of  the  swallow,  there  is  a curious  resem- 
blance to  the  human  arm,  and  we  cannot  fail  to 
observe,  that  the  pectoral  muscle  constitutes  the 
greater  part  of  the  bulk  of  the  body.*  -A.nd  here  we 
see  the  correspondence  between  the  strength  of  this 
muscle  and  the  rate  of  flying  of  the  swallow,  which 
is  a mile  in  a minute,  for  ten  hours  every  day,  or  six' 
hundred  miles  a day.f  If  it  be  true  that  birds,  when 
migrating,  require  a wind  that  blows  against  them, 
it  implies  an  extraordinary  power,  as  well  as  continu- 
ance of  muscular  exertion. 

We  see  how  Nature  completes  her  work,  rvhen  the 
intention  is  that  the  animal  shall  rise  buoyant  and 
powerful  in  the  air  : — the  whole  texture  of  the  frame 
is  altered  and  made  light,  in  a manner  consistent 
witli  strength.  We  see  also  how  the  mechanism  of 
the  anterior  extremity  is  changed,  and  the  muscles 
of  the  trunk  difl’erently  directed.  But  we  are 
tempted  to  examine  those  means,  which  we  would 
almost  say  are  more  awkwardly  suited  for  their  pur- 
pose, where  the  system  of  bones  and  muscles,  pecu- 
liar to  the  quadruped,  is  preserved,  while  a power  of 
launching  into  the  air  is  also  given.  We  have  already 


* Borelli  makes  the  pectoral  muscles  of  a bird,  exceed  in  weight 
all  the  other  muscles  taken  together;  wliilst  the  pectoral  muscles  of 
man,  are  but  a seventieth  part  of  the  whole  mass  of  the  muscles. 

t Mr.  White  says  truly,  that  the  swift  lives  on  the  wing;  it  eats, 
drinks,  and  collects  materials  for  its  nest  in  flying,  and  na\-er  r ests 
but  during  darkness. 


roR  FLVIJsG, 


07 


noticed  the  structure  of  the  bat  as  adapted  to  flight ; 
but  there  are  other  animals  which  enjoy  this  function 
in  a lesser  degree.  For  example,  the  flying  squirrel 
(Petromys  Volucella),  being  chased  to  the  end  of  the 
bough,  spreads  out  its  mantle  from  one  extremity  to 
the  other,  and  ch'ops  in  the  air  ; but  with  such  a re- 
sistance from  its  extended  skin  and  its  tail,  that  it 
can  direct  its  flight  obliquely  downwards,  and  even 
turn  in  the  air.  But  to  this  end,  there  is  no  necessity 
for  any  adaptation  of  the  anterior  extremity.  Among 
reptiles  there  is  a provision  of  the  same  kind,  in  the 
Draco  fimbriatus  ; which  is  capable  of  creeping  to  a 
height,  and  dropping  safely  to  the  ground,  under  the 
protection  of  a sort  of  parachute,  formed  by  its  ex- 
tended skin.  This  is  not  an  inapt  illustration,  for 
although  the  phalanges  of  the  fingers  ai'e  not  here 
used  to  extend  the  web,  the  ribs,  which  are  unneces- 
sary for  breathing,  are  prolonged  like  the  whalebone 
of  an  umbrella,  and  on  them  the  skin  is  expanded. 

But  this  brings  us  to  a very  curious  subject, — the 
condition  of  those  Saurian  reptiles,  the  remains  of 
which  are  found  onl}^  in  a fossil  state,  in  what  are 
termed  the  ancient  strata  of  the  Jura.  The  Ptero- 
dactyle  of  Cuvier  is  an  animal  which  seems  to  con- 
found all  our  notions  of  system.  Its  mouth  was  like 
the  long  bill  of  a bird,  and  its  flexible  neck  corre- 
sponded ; but  it  had  teeth  in  its  jaws  like  those  of  a 
crocodile.  It  liad  the  bones  of  the  anterior  extremit}’ 
prolonged,  and  fashioned  somewhat  like  those  in  the 
wing  of  a bird  ; but  it  could  not  have  had  feathers, 
as  it  had  not  a proper  bill.  We  see  no  creature  hav- 
ing feathers  without  a bill  to  dress  and  prim  them. 
Nor  did  this  extremity  resemble  the  structure  in  that 
of  a bat ; instead  of  the  phalanges  being  equalty 
prolong'ed,  the  second  only  was  extended  to  an  ex- 
traordinary length,  whilst  the  third,  fourth,  and  fifth 
remained  with  the  length  and  articulation  of  a quad- 
ruped, and  with  sharp  nails,  corresponding  with  the 
pointed  teeth.  The  extended  metacarpal  bone 


68 


ANATOMY  OF 


reached  double  the  whole  length  of  the  animal,  and 
the  conjecture  is,  that  upon  it  was  extended  a mem- 
brane, resembling  that  of  the  Draco  fimbriatus.  In 
the  imperfect  specimens  which  we  have,  we  cannot 
discover  in  the  height  of  the  pelvis,  the  strength  of 
the  vertebrae  of  the  back,  or  the  expansion  of  the 
sternum,  a provision  for  the  attachment  of  muscles 
commensurate  with  the  extent  of  the  supposed  wing. 
The  humerus,  and  the  bones,  which  we  presume  are 
the  scapula  and  coracoid,  bear  some  correspondence 
to  the  extent  of  the  wing  ; but  the  extraordinary 
circumstance  of  all,  is  the  size  and  strength  of  the 
bones  of  the  jaw  and  vertebrae  of  the  neck,  compared 
with  the  smallness  of  the  body,  and  the  exti’eme  deli- 
cacy of  the  ribs ; which  make  it,  altogether-,  the 
thing  nrost  incomprehensible  in  nature. 


OF  THE  RADIUS  AND  ULNA. 

The  easy  motion  of  the  hand,  we  might  imagine  to 
be  in  the  hand  itself ; but,  on  the  contrary,  the  move- 
ments which  appear  to  belong  to  it,  are  divided 
among  all  the  bones  of  the  extremity.* 

The  head  of  the  humerus  is  rotatory  on  the  sca- 
pula, as  when  making  the  guards  in  fencing ; but 
the  easier  and  finer  rolling  of  the  wrist  is  accom- 
plished by  the  motion  of  the  radius  on  the  ulna. 

The  ulna  has  a hooked  process,  the  olecranorr, 
which  catches  round  the  lower  end  of  the  humerus 
or  arm  bone,  (this  articulating  portion  is  called  tro- 
chlea), and  forms  with  it  a hinge  joint.  The  radius, 
again,  has  a small,  neat,  round  head,  which  is  bound 
to  the  ulna  by  ligaments,  as  a spindle  is  held  in  the 
buslr.  This  bone  turns  on  its  axis  and,  as  it  turns. 


♦ In  the  sketch  in  the  next  page,  the  upper  bone  of  the  fore-ami  is 
the  radius,  and  in  revolving  on  the  lorver  bone,  tlie  ulna,  it  carries 
the  hand  with  it. 


THE  F0EE-AR5I. 


69 


carries  the  hand  with  it,  because  the  hand  is  stnctly 
attached  to  its  lower  head  alone.  This  rolling",  is 
what  is  termed  pronation  and  supination. 


Such  a motion  would  be  useless,  and  a source  of 
weakness  in  an  animal  that  had  a solid  hoof.  Ac- 
cordingl}^,  in  the  horse,  these  bones  are  united 
together  and  consolidated  in  the  positon  of  pronaticm 


70 


ANATOMY  OF 


I(.  is  interesting  to  find  that  by  studpng  the  pro- 
cesses of  the  bones,  than  which  nothing,  at  first 
sight,  appears  more  inconsequent,  we  are  learning  the 
characters  of  a language  which  shall  enable  us  to 
read  monuments  of  the  highest  interest ; — the  records 
of  the  creation,  which  give  an  account  of  the  revo- 
lutions of  the  earth  itself. 

If  a geologist  should  find  the  nearer  head  of  the 
radius,  and  see  in  the  extremity  of  it  a smooth  de- 
pression, where  it  bears  against  the  hiunerus,  and 
observe  the  polished  circle  that  turns  on  the  ca^^ty 
of  the  ulna, — he  would  say, — This  animal  had  a 
paw — it  had  a motion  at  the  wrist,  which  implies 
claws.  Claws  may  belong  to  two  species  of  animals  ; 
the  feline,  which  is  possessed  of  sharp  carnivorous 
teeth,  or  to  animals  without  teeth.  If  he  should 
find  the  lower  extremity  of  this  same  bone,  and  ob- 
serve on  it  spines  and  grooves  for  the  distinct  tendons 
which  disperse  to  the  phalanges,  he  would  conclude 
that  there  must  have  been  moveable  claws — that  it 
belonged  to  a carnivorous  animal ; and  he  would 
seek  for  canine  teeth  of  a corresponding  size. 


OF  THE  WRIST  AND  HAND. 

In  the  human  hand,  the  bones  of  the  wrist  (car- 
pus) are  eight  in  number ; and  they  are  so  closely 
connected  that  they  form  a sort  of  ball,  which  moves 
on  the  end  of  the  radius.  Be5mnd  these,  and  to- 
wards the  fingers  are  the  metacarpal  bones,  which 
diverge  at  their  further  extremities,  and  give  support 
to  the  bones  of  the  fingers.  The  thumb  has  no  me- 
tacarpal bone,  and  is  directly  articulated  with  the 
carpus  or  wrist.  There  are  thus  in  the  hand  twent)'- 
nine  bones,  from  the  mechanism  of  which,  result 
strength,  mobility,  and  elasticity. 

Lovers  of  system  (I  do  not  use  the  term  disparag- 
ingly) delight  to  trace  the  gradual  substraction  of  the 


THE  WRIST  AND  HAND. 


71 


bones  of  the  hand.  Thus,  looking  to  the  liand  of 
man,  they  see  the  thumb  fully  formed — in  the  simiae 
they  find  it  exceedingly  small ; in  one  of  them,  the 
spider-monkey,  it  has  disappeared,  and  the  four  fin- 
gers are  sufficient,  with  hardly  the  rudiments  of  a 
thumb.  In  some  of  the  tardigrade  animals,  there 
are  only  three  metacarpal  bones  with  their  fingers. 
In  the  horse,  the  cannon  bone  may  be  shewn  to 
consist  of  two  metacarpal  bones.  Indeed,  we  might 
go  further  and  instance  the  wing  of  the  bird.  To 
me,  this  appears  to  be  losing  the  sense,  in  the  love 
of  system.  There  is  no  regular  gradation,  but  a 
variety,  most  curiously  adapting,  as  I have  often  to 
repeat,  the  same  system  of  parts  to  every  necessary 
purpose. 

In  a comparative  view  of  these  bones,  we  are  led 
more  particularly  to  notice  the  foot  of  the  horse  ; it 
is  universally  admitted  to  be  of  a beautiful  design, 
and  calculated  for  strength  and  elasticity,  and  espe- 
cially provided  against  concussion. 

The  bones  of  the  fore-leg  of  the  horse  become 
firmer  as  we  trace  them  downwards.  The  two  bones 
corresponding  with  those  of  the  fore-arm,  are  braced 
together  and  consolidated ; and  the  motion  at  the 
elbow  joint  is  limited  to  flexion  and  extension.  The 
carpus,  forming  what  by  a sort  of  license  is  called 
the  knee,  is  also  new  modelled  ; but  the  metacarpal 
bones  and  phalanges  of  the  toes  are  totally  changed, 
and  can  hardly  be  recognized.  When  we  look  in 
front,  instead  of  the  four  metacarpal  bones,  we  see 
one  strong  bone,  the  cannon  bone,  and  posterior  to 
this,  we  find  two  lesser  bones,  called  splint  bones. 
The  heads  of  these  lesser  bones  enter  into  the  knee- 
joint  ; but  at  their  lower  ends  they  diminish  gra- 
dually, and  they  are  held  by  an  elastic  ligamentous 
attachment  to  the  sides  of  the  cannon  bone. 

I have  some  hesitation  in  admitting  the  correct- 
ness of  the  opinion  of  veterinary  surgeons  of  this  cu- 
rious piece  of  mechanism.  They  imagine  that  these 


73 


ACTION  OF  THE  SPLINT  BONES. 


moveable  splint  bones,  by  playing  up  and  down, 
as  the  foot  is  alternately  raised  and  pressed  to  the 
ground,  bestow  elasticity  and  prevent  concussion. — 
The  fact  certainly  is,  that  by  over  action  this  part  be- 
comes inflamed,  and  the  extremities  are  preternatu- 
rally  jomed  by  bone  to  the  greater  metacarpal  or  can- 
non bone  ; and  that  this,  which  is  called  a splint, 
is  a cause  of  lameness. 

I suspect,  rather,  that  in  the  perfect  state  of  tlie 
joint,  these  lesser  metacarpal  bones  act  as  a spring 
to  throw  out  the  foot,  when  it  is  raised  and  the  knee- 
ioiiit  bent.  If  we  admit  that  it  is  the  quickness  in 
tile  extension  of  this  joint  on  which  the  rate  of  motion 
must  principally  depend,  it  will  not  escape  observa- 
tion, that  in  the  bent  position  of  the  knee,  the  exten- 
sor tendons  liave  very  little  power,  owing  to  their 


IN  THE  horse’s  LEG. 


73 


running  so  near  the  centre  of  motion  in  the  joint; 
and  that,  in  fact,  they  require  some  additional  means 
to  aid  the  extension  of  the  leg. 

Suppose  that  the  head  of  the  lesser  metacarpal 
bone  A enters  into  the  composition  of  the  joint,  it  does 
not  appear  that  by  its  yielding,  when  the  foot  is 
upon  the  ground,  the  bones  of  the  carpus  can  de- 
scend, as  long  as  they  are  sustained  by  the  greater 
metacarpal  or  cannon  bone.  I do  not,  therefore, 
conceive  that  this  bone  can  add  to  the  elasticity  of 
the  foot.  But  when  we  perceive  that  the  head  of  the 
splint  bone  is  behind  the  centre  of  motion  in  the  joint, 
it  is  obvious  that  it  must  be  more  pressed  upon,  in 
the  bent  condition  of  the  joint  when  the  foot  is  eleva- 
ted, and  that  then,  the  bone  must  descend.  If  it  be 
depressed  when  the  foot  is  raised,  and  have  a power  of 
recoiling  (which  it  certainly  has)  it  must  aid  in  throw- 
ing out  the  leg  into  the  straight  position  and  assist  the 
extensor  muscles.  Further,  we  can  readily  believe 
that  when  the  elasticity  of  these  splint  bones  is  lost, 
by  ossification  uniting  them  firmly  to  the  cannon  bone, 
the  want  of  such  a piece  of  mechanism,  essential  to 
the  quick  extension  of  the  foot,  will  make  the  horse 
apt  to  come  down. 

In  looking  to  this  sketch,  and  comparing  it  with 
that  of  the  hand  on  page  69,  we  see  that  in  the 
horse’s  leg  the  five  bones  of  the  first  digital  phalanx 
are  consolidated  into  the  large  pastern  bone ; those 
of  the  second  phalanx,  into  the  lesser  pastern  or 
coronet ; and  those  of  the  last  phalanx,  into  the  cofiin 
bone. 

Of  THE  horse’s  foot. — But  the  foot  itself  de- 
serves our  attention.  The  horse,  a native  of  exten- 
sive plains  and  steppes,  is  perfect  in  his  structure,  as 
adapted  to  these,  his  natural  pasture  grounds.  When 
brought,  however,  into  subjection,  and  running  on  om- 
hard  roads,  his  feet  suffer  from  concussion.  The 
value  of  the  horse,  so  often  impaired  by  lameness  of 
the  foot,  has  made  that  part  an  olrject  of  great  inter- 


74 


OF  THE  horse’s  FOOT. 


est : and  I have  it  from  the  excellent  professor  of  ve- 
terinary surgery  to  say,  that  he  has  never  demon- 
strated the  anatomy  of  the  horse’s  foot  without  find- 
ing something  new  to  admire. 

The  weight  and  power  of  the  animal  require  that 
he  should  have  a foot  in  which  strength  and  elasti- 
city are  combined.  The  elasticity  is  essentially  ne- 
cessary to  prevent  percussion  in  striking  the  ground  ; 
and  it  is  attained  here,  through  the  united  effect  of 
the  oblique  position  of  the  bones  of  the  leg  and  foot 
— the  yielding  nature  of  the  suspending  ligament, 
and  the  expansibility  of  the  crust  or  hoof.  So  much 
depends  on  the  position  of  the  pastern  bones  and 
coffin  bone,  that  judging  by  the  length  of  these  and 
their  obliquity,  it  is  possible  to  say  whether  a horse 
goes  easily,  without  mounting  it.  When  the  hoof 
is  raised,  it  is  smaller  in  its  diameter,  and  the  sole  is 
concave  ; but  when  it  bears  on  the  ground  it  expands, 
the  sole  descends  so  as  to  become  flatter  ; and  this 
expansion  of  the  hoof  laterally,  is  necessary  to  the 
play  of  the  whole  structure  of  the  foot.  Hence  it 
happens  that  if  the  shoe  be  nailed  in  such  a manner 
as  to  prevent  the  hoof  expanding,  the  whole  interior 
contrivance  for  mobility  and  elasticity  is  lost.  The 
foot,  in  trotting,  comes  down  solid,  it  consequently 
suffers  percussion  ; and  from  the  injury,  it  becomes 
inflamed  and  hot.  From  this  inflammation  is  gene- 
rated a variety  of  diseases,  which  at  length  destroy 
all  the  beautiful  provision  of  the  horse’s  foot  for  free 
and  elastic  motion. 

This  subject  is  of  such  general  interest,  that  I may 
venture  on  a little  more  detail.  The  elastic  or 
suspending  ligament  spoken  of  above,  passes  down 
from  the  back  of  the  cannon  bone,  along  all  the 
bones,  to  the  lowest,  the  coffin  bone ; it  yields,  and 
allows  these  bones  to  bend.  Behind  the  hgament 
the  great  tendons  run,  and  the  most  prolonged  of 
these,  that  of  the  perforans  muscle,  is  principally 
inserted  into  the  coffin  bone,  having  at  the  same  time 


OF  THE  horse’s  FOOT. 


75 


other  attachments.  Under  the  hones  and  tendon,  at 
the  sole  of  the  foot,  there  is  a soft  elastic  cushion  ; 
this  cushion  rests  on  the  proper  horny  frog,  that 
prominence  of  a triangular  shape  which  is  seen  izi 
the  hollow  of  the  sole.  The  soft  elastic  matter  being 
pressed  down,  shifts  a little  backwards,  so  that  it 
expands  the  heels  at  the  same  time  that  it  hears  on 
the  frog,  and  presses  out  the  lateral  part  of  the  crust. 
We  perceive  that  there  is  a necessity  for  the  bottom 
of  the  hoof  being  hollow  or  concave — first,  to  prevent 
the  delicate  apparatus  of  the  foot  from  being  bruised, 
and,  secondly,  that  elasticity  may  be  obtained  by  its 
descent.  We  see  that  the  expansion  of  the  hoof,  and 
the  descent  of  the  sole  are  necessary  to  the  play  of 
the  internal  apparatus  of  the  foot. 

That  there  is  a relation  between  the  internal  struc- 
ture and  the  covering,  whether  it  be  the  nail,  or  crust, 
or  hoof,  we  can  hardly  doubt : and  an  unexpectecl 
proof  of  this  offers  itself  in  the  horse.  There  are 
some  very  rare  instances  of  a horse  having  digi- 
tal extremities.  According  to  Suetonius,  there  was 
such  an  animal  in  the  stables  of  Caesar ; another 
was  in  the  possession  of  Leo  X. ; and  Geoffrey  St. 
Hilaire,  in  addition  to  those,  says,  that  he  has  seen  a 
horse  with  three  toes  on  the  fore-foot,  and  four  on 
the  hind-foot.*'  These  instances  of  deviation  in  the 
natural  structure  of  the  bones  were  accompanied 
with  a corresponding  change  in  the  coverings — the 
toes  had  nails,  not  hoofs. 

By  these  examples,  it  is  made  to  appear  still  more 
distinctly  that  there  is  a relation  between  the  inter- 
nal configuration  of  the  toes  and  their  coverings — 
that  when  there  are  five  toes  complete  in  their  bones, 
they  are  provided  with  perfect  nails — when  two  toes 
represent  the  whole,  as  in  the  cleft  foot  of  the  rumin- 


* Such  a horse  -svas  not  long  since  exhibited  in  Town  and  at 
Newmarket. 


76 


FOOT  OF  EUMINANTS. 


ant,  there  are  appropriate  horny  coverings — and  that 
when  the  bones  are  joined  to  form  the  pastern  bones 
and  coffin  bone,  there  is  a hoof  or  crust,  as  in  the 
horse,  conagga,  zebra,  and  ass. 

In  ruminants  there  is  a cannon  bone,  but  the  foot 
13  split  into  tAvo  parts,  and  this  must  add  to  its  spring 
or  elasticity.  I am  inclined  to  think  that  there  is  still 
another  intention  in  this  form ; it  prevents  the  foo^ 
sinking  in  soft  ground,  and  pemiits  it  to  be  more 
easily  AvithdraAvn.  We  may  observe  how  much 
more  easily  the  coav  withdraws  her  foot  from  the 
yielding  margin  of  a rwer,  than  the  horse.  The 
round  and  concave  form  of  the  horse’s  foot  is  attended 
Avith  a vacuum  or  suction,  as  it  is  Avithdrawn  ; AA'hile 
the  split  and  conical  shaped  hoof  expands  in  sinking, 
and  is  easily  extricated. 

In  the  chamois  and  other  species  of  the  deer  there 
is  an  additional  toe.  A sort  of  lesser  cannon  bone, 
with  its  two  pasterns,  supports  this  toe,  and  is  joined 
by  ligament,  to  the  larger  cannon  bone,  so  that  it 
must  have  great  elasticity.  As  a division  of  the 
flexor  tendon  runs  into  it,  it  must  increase  (he  spring 
Avlien  the  animal  rises  from  its  crouching  position. 
We  see,  in  these  sketches,  that  the  lesser  metacarpal 
bone,  Avhich,  in  the  horse,  entered  into  the  joint  of 
the  “ knee,”  is  here  brought  doAA'n  to  increase  the 
elasticity,  or  to  expand  the  foot. 

The  tAvo  lateral  toes  of  the  hog  are  short,  and  do 
not  touch  the  ground,  yet  the^'^  must  serve  to  sustain 
the  animal  Avhen  the  foot  sinks.  In  the  rein-deer 
these  bones  are  strong  and  deep,  and  the  toe,  by  pro- 
jecting backAA'ards,  extends  the  foot  horizontally — 
thus  giving  the  animal  a broader*  base  to  stand  on, 
and  adapting  it  to  the  snows  of  Lapland,  on  the  prin- 
ciple of  the  snoAV-shoe.  The  systematic  naturalist 
Avil!  call  these  changes  in  the  size,  number,  and  place 
of  the  metacarpal  bones  “ gradations I see  m 
tlrem  only  new  proofs  of  the  same  sA'stem  of  bones 
being  applicable  to  every  circumstance,  or  conditioit 


ELEPHANT  AND  CAMEL. 


77 


of  animals,  and  furnishing  us  with  other  instances  of 
adaptation. 

I have  explained  why  I think  that  the  bones  of  the 
elephant’s  leg  stand  so  perpendicularly  over  each 
other ; there  is  a peculiarity  also  in  the  bones  of  the 
foot.  In  the  foot  of  the  living  animal  we  see  only  a 
round  pliant  mass,  which,  when  he  stands,  resembles 
the  base  of  a pillar,  or  the  lower  part  of  the  trunk  of 
a stately  tree.  But  when  we  examine  the  bones  of 
the  foot,  we  find  this  broad  base  to  consist  of  the  car- 
pus, metacarpus,  and  phalanges  of  the  toes  ; and 
these  bones  have  a very  different  use  from  what  we 
have  hitherto  noticed.  They  are  not  connected  with 
a moveable  radius,  and  have  no  individual  motion,  as 
in  the  carnivorous  animal — they  merely  serve  to  ex- 
pand the  foot,  the  base  of  the  column,  and  to  give  it 
a certain  elasticity. 

In  page  53  I have  noticed  the  bones  of  the  foot 
of  the  camel  in  contrast  with  those  of  the  elephant. 
The  camel’s  foot  having  no  such  disproportioned 
weight  to  bear  as  in  the  elephant,  lightness  of  motion 
is  secured  by  the  oblique  position  of  its  bones,  as  well 
as  by  the  direction  of  the  bones  of  the  shoulder, 
which  we  have  formerly  noticed.  In  the  soft  texture 
of  the  camel’s  foot  there  is  much  to  admire  ; for 
although  the  bottom  be  flat,  like  the  sole  of  a shoe, 
yet  there  is  between  it  and  the  bones  and  tendons  a 
cushion,  so  soft  and  elastic  that  the  animal  treads 
with  great  lightness  and  security.  The  resemblance 
of  the  foot  of  the  ostrich  to  that  of  the  camel  has  not 
escaped  naturalists. 

We  are  now  treating  of  the  last  bones  of  the  toes  ; 
and  let  us  see  what  may  be  done,  by  the  study  of  one 
of  these  bones,  to  the  bodying  forth  of  the  whole 
animal.  I allude  to  the  dissertations  of  the  President 
Jefferson  and  Baron  Cuvier  on  the  Megalonix.  But 
we  must  preface  this  part  of  our  subject  by  some 
remarks  on  the  form  of  the  claws  of  the  lion. 

The  canine  tribe  are  carnivorous,  like  the  feline, 
7*  . 


78 


MECHANISM  OF 


* 


and  both  have  the  last  bones  of  their  toes  anned  with 
a nail  or  claw.  But  their  habits  and  their  means  of 
obtaining  food  are  different.  The  first  combine  a 
keen  sense  of  smelling  with  a power  of  continued 
speed  ; they  run  down  their  prey.  The  feline  order 
have  their  superiority  in  the  fineness  of  their  sight, 
accompanied  with  a patience,  watchfulness,  and 
stealthy  movement  ; they  spring  upon  their  prey, 
and  never  long  pursue  it.  They  attain  their  object 
in  a few  bounds,  and,  failing,  sulkily  resume  their 
watch.  When  we  look  to  the  claws,  we  see  a cor- 
respondence with  those  habits.  The  claws  of  the 
dog  and  wolf  are  coarse  and  strong,  and  bear  the 
pressure  and  friction  incident  to  along  chase.  Thev 
are  calculated  to  sustain  and  protect  the  foot.  But 
the  tiger  leaps  on  his  prey,  and  fastens  his  sharp  and 
crooked  claws  in  the  flesh.  These  claws  being 
curved  and  sharp,  we  must  admire  the  mechanism 
by  which  they  are  preserved.  The  last  bone,  that 
which  supports  the  claw,  is  placed  lateral  to  the 
penultimate  bone,  and  is  so  articulated  with  it,  that 
an  elastic  ligament  (a)  draws  it  back  and  raises  the 
sharp  extremity  of  the  claw  upwards.  The  nearer 
extremity  of  the  furthest  bone  presses  the  ground 
in  the  ordinary  running  of  the  animal,*  whilst  the 

* The  pads  in  the  bottom  of  the  lion’s  foot  cover  these  bones,  or 
rather,  we  should  say,  protect  them ; they  are  soft  cusliions,  which 
add  to  the  elasticity  of  the  foot,  and  must,  in  some  degree,  defend  the 
animal  in  alighting  from  its  boimd.  I could  not  comprehend  how  the 
powerful  flexor  muscles  did  not  unsheath  the  claws  when  the  lion 
made  its  spring,  and  how  they  produced  this  effect  when  there  was 
an  excitement  to  seize  and  hold  the  prey — 1 made  tliis  dissection  to 
detect  the  cause.  The  last  bone  of  die  toe  is  placed  in  a manner  so 
peculiar  in  relation  to  the  pemiltiniate,  being  drawn  back  by-  the 
elastic  ligament  (a)  beyond  the  centre  of  motion  of  thejoint,  that  the 
flexor  tendon  (b)  acting  upon  it,  forces  the  nearer  end,  and  the  cush- 
ion of  the  toe  to  the  ground.  But  when  a more  general  excitement 
takes  place  in  the  muscles  called  interossei,  and  the  extensors,  n,  e, 
the  relative  position  of  the  two  last  bones  is  altered ; so  that  the  action 
of  the  flexor  tendon  can  now  draw  forwaid  the  last  bone — thus 
unsheathing  and  uncovering  the  daw,  and  preparing  it  to  hold  or  to 
tear. 


THE  LION  S CLAW. 


7D 


claw  is  thus  retracted  into  a sheatli.  But  when  the 
tiger  makes  his  spring,  the  claws  are  uncased  by  the 
action  of  the  flexor  tendons  ; and  they  are  so  sharp 
and  strong  in  the  Bengal  tiger,  and  his  arm  is  so 
powerful,  that  they  have  been  known  to  fi'acture  a 
man’s  skull  by  a touch,  in  the  act  of  leaping  over 
him. 

I have  alluded  to  the  observation  of  President  Jef- 
ferson on  the  JMegalonix.  Having  found  a bone, 
which  by  its  articulating  surface  and  general  form, 
he  recognised  to  be  one  of  the  bones  of  the  phalanx 
of  an  animal  of  great  size,  he  thought  he  could  dis- 
cover that  it  had  carried  a claw  ; and  from  this  cir- 


80 


ON  THE  MEGALONIX. 


cumstance,  he  naturally  enough  concluded  (accord- 
ing to  the  adage — ex  ungue  leonem)  that  it  must 
have  belonged  to  a carnivorous  animal.  He  next  set 
about  calculating  the  length  of  this  claw,  and  estima- 
ting the  size  of  the  animal.  He  satisfied  himself 
that  in  this  bone,  a relic  of  the  ancient  world,  he  had 
obtained  a proof  of  the  existence,  during  these  old 
times,  of  a lion  of  the  height  of  the  largest  ox,  and 
an  opponent  fit  to  cope  with  the  mastodon.  But 
when  this  bone  came  under  the  scrutiny  of  Baron 
Cuvier,  his  perfect  knowledge  of  anatomy  enabled  him 
to  draw  a different  conclusion. 

He  first  observed  that  there  was  a spine  in  the 
middle  of  the  articulating  surface  of  the  last  bone, 
which  in  this  respect  was  unUke  the  form  of  the 
same  bone  in  the  feline  tribe.  He  found  no  provi- 
sion in  this  specimen  of  an  extinct  animal,  for  the 
lateral  attachment  of  the  bone,  wdiich  we  have  just 
noticed  to  be  necessary  for  its  retraction.  Then  ob- 
serving what  portion  of  a circle  this  bone  formed,  he 
prolonged  the  line,  and  showed  that  the  claw  belong- 
ing to  it  must  have  been  of  such  great  length,  that 
it  could  never  have  been  retracted  to  the  effect  of 
guarding  an  acute  and  sharp  point.  The  point, 
therefore,  could  not  have  been  raised  verticall)^  so  as 
to  have  permitted  the  animal  to  put  the  foot  to  the 
ground  without  blunting  the  instrument  ! Pursuing 
such  a comparison,  he  rejected  the  idea  of  the  bone 
belonging  to  the  feline  tribe  at  all.  His  attention 
was  directed  to  another  order,  the  paresseux  or  sloths, 
which  have  great  toes  and  long  nails.  Their  nails 
are  folded  up  in  a different  fashion  ; they  just  enable 
the  animal  to  walk  ; but  slowly  and  awkwardly, 
something  in  the  same  manner  as  if  we  were  to  fold 
our  fingers  on  the  palm  of  the  hand,  and  bear  upon 
our  knuckles.  On  instituting  a more  just  compari- 
son between  these  bones  of  the  ancient  animal,  and 
the  corresponding  bones  of  the  paresseux,  he  has 
satisfied  us,  that  the  lion  of  the  American  President 


FOOT  OF  THE  QUADRUMANA. 


81 


was  an  animal  which  scratched  the  ground  and  fed 
on  roots. 

One  experiences  something  like  relief  to  find  that 
there  never  was  such  an  enormous  carnivorous  ani- 
mal as  this,  denominated  megalonix. 

These  finger-bones,  or  bones  of  the  claws,  exhibit 
a very  remarkable  correspondence  with  the  habits 
and  general  fonns  of  animals.  Besides  what  we 
have  seen  in  the  lion,  or  tiger,  in  the  dog,  and  wolf, 
in  the  bear  and  ant-eater,  there  is  a variety,  where 
we  should  least  expect  it,  in  the  animals  that  live  in 
woods,  and  climb  the  branches  of  trees.  The  squir- 
rel, with  claws  set  both  ways,  runs  with  equal  facility 
up  and  doAvn  the  bole,  and  nestles  in  the  angles  of 
the  branches.  The  monkey  leaps  and  swings  him- 
self from  branch  to  branch,  and  springing,  parts  with 
his  hold  by  the  hinder  extremities  before  he  reaches 
with  the  anterior  extremities  ; he  leaps  the  interven- 
ing space,  and  catches  with  singular  precision.  But 
the  sloths  do  not  grasp  ; their  fingers  are  like  hooks, 
and  their  strength  is  in  their  arms.  They  do  not 
hold,  but  hang  to  the  branch.  They  never  let 
go  with  one  set  of  hooks,  until  they  have  caught 
with  the  other,  and  thus  they  use  both  hind  and 
fore  feet,  whilst  their  bodies  are  pendant.  Here, 
once  more,  we  see  the  form  of  the  extremity,  the 
concentration  of  strength,  and  the  habit  of  ani- 
mals, conforming  not  merely  to  their  haunts  in  the 
forest,  but  to  their  mode  of  moving  and  living  among 
the  branches;  all  active,  but  in  a different  manner. 

There  have  been  of  late  deposited  in  our  Museum 
in  the  College  of  Surgeons,  the  bones  of  an  animal  of 
great  size ; and  the  examination  of  these  gives  us  an 
opportunity  of  applying  the  principles  and  the  mode  of 
investigation  followed  by  our  great  authority  in  this 
part  of  science. 

These  remains  consist  of  part  of  the  head,  spine, 
tail,  pelvis,  and  the  bones  of  one  hinder  extremity, 
and  the  scapula.  Esthnating  the  animal  at  seven 


82 


MEGATHERIUM. 


feet  in  height,  it  scarcely  conveys  an  adequate  idea 
of  its  size  ; for  the  thigh-bone  is  three  times  the  di- 
ameter of  that  of  the  large  elephant  which  is  in  the 
same  collection,  and  the  pelvis  is  twice  the  breadth 
of  that  of  the  same  animal.  Forming  our  opinion 
on  these  principles  to  which  we  have  had  repeated 
occasion  to  refer  in  this  essay,  and  judging  by  the 
strength  and  prominence  of  the  processes  of  these 
bones,  the  animal  must  have  possessed  great  muscu- 
lar power  ; and  directed  by  the  same  circumstances 
still,  we  can  form  an  idea  of  the  manner  in  which 
that  muscular  power  was  employed. 

On  comparing  these  bones  with  the  drawings  of 
the  skeleton  of  the  enormous  animal  preserved  in  the 
Royal  Museum  of  Madrid,  it  is  seen  at  once  that  this 
new  acquisition  is  part  of  the  remains  of  the  great 
animal  of  Paraguay,  the  Megatherium  of  Cuvief. 
Every  observation  which  we  are  enabled  to  make  on 
the  extreme  bones  of  the  foot,  on  the  scapula,  and  on 
the  teeth,  confirms  the  idea  entertained  by  Cuviei,  that 
it  was  a vegetable  feeder  ; and  that  its  great  strength 
was  employed  in  flinging  up  the  soil  and  digging  for 
roots.  Its  strength  seems  to  have  been  concentra- 
ted to  its  paws,  corresponding  with  the  provisions 
there  for  enormous  nails  or  claws.  I have  heard  it 
surmised  that  this  animal  may  have  sat  upon  its 
hinder  extremities,  and  pulled  down  the  branches  of 
trees  to  feed  upon.  It  is  only  its  great  size  that  can 
countenance  such  an  idea.  We  have  not  the  hu- 
merus, which  by  its  processes  would  have  declared 
the  classification  and  activity  of  its  muscles  ; but  we 
can  estimate  the  height,  breadth,  and  strength  of  the 
animal  by  the  pelvis  and  enonnous  bones  of  the  pos- 
terior extremity  ; while  by  the  scapula  and  clavicle 
we  can  form  a conception  of  the  extent  of  motion  of 
the  anterior  extremity,  and  the  great  power  that  it 
possessed.  In  short,  by  the  osseous  and  muscular 
S3’^stems  we  perceive  that  the  strength  was  not  so 
jniicli  in  the  body,  certainh’"  not  in  the  jaws,  but  was 


AMPHIBIA. 


83 


directed  rather  to  the  extremities ; and  that  it  was 
given  neither  for  rapidity  of  motion  nor  defence,  but 
for  digging. 

How  little  was  it  to  be  expected  that  an  alliance 
between  anatomy,  the  most  despised  part  of  it,  and 
mineralogy,  was  to  give  rise  to  a new  science ; — 
making  a part  of  natural  history  which  had  been  pur- 
sued in  mere  idleness,  vaguely,  and  somewhat  fanci- 
fully, to  be  henceforth  studied  philosophically,  and  by 
inductive  reasoning.  It  is  both  interesting  and  in- 
instructive  to  find  the  relations  thus  established  be- 
tween departments  of  knowledge  apparently  so  re- 
mote. 

In  the  true  Amphibia,  as  the  phoca  and  walrus, 
we  have  the  feet  contracted,  and  almost  enveloped  in 
the  skin,  and  the  fingers  webbed  and  converted  into 
fins. 


84 


BONES  IN  THE  CETACEA. 


We  have  sketched  here,  the  bones  of  the  morse, 
or  walrus,  and  they  are  remarkably  complete,  if  we 
consider  the  appearance  of  the  feet  in  the  living  ani- 
mal. The  bones  are  here  accommodated  to  an  in- 
strument for  swimming  ; for  these  animals  live  in 
the  water,  and  come  to  land  only  to  suckle  their 
young,  or  to  bask  in  the  sun  ; and  they  are  the  most 
unwieldy  and  helpless,  out  of  the  water,  of  all  ani- 
mals which  breathe. 

In  the  Cetacea,  we  have  mammalia  without  hind 
feet.  The  scapula  is  large,  the  humerus  very  short, 
and  the  bones  of  the  fore-arm  and  hand  flattened 
and  confined  in  membranes  which  convert  them  into 
a fin.  They  live  in  the  water,  but  must  rise  to 
breathe. 

I need  not  say  that  in  the  dolphin  we  recognize 
the  bones  of  the  anterior  extremit)^,  only  a little  fur- 
ther removed  from  the  forms  which  we  have  hitherto 
been  contemplating.  The  seal  and  morse  raise  them- 
selves out  of  the  water  and  lie  on  the  rocks  ; the  dif- 
ferent species  of  the  dolphin  continue  always  in  the 
the  water  ; the  extremity  is  now  a fin  or  an  oar,  and 
those  who  have  seen  the  porpoise  or  the  pelloch  in  a 
stormy  sea,  must  acknowledge  how  complete  the 
apparatus  is,  through  which  they  enjoy  their  element. 

The  last  examples  I select,  shall  be  from  the  an- 
cient world.* 


* The  figure  to  the  left  is  the  anterior  extremity  of  the  Plesiosau- 
rus ; to  the  right  tliat  of  the  Ichthyosaurus.  In  these  paddles  we 
see  the  intermediate  changes  from  the  foot  of  land  animals  to  the  fin 
of  the  fish. — The  walrus,  dolphin,  turtle,  plesiosaurus,  iclithyosaurus 
— where  we  no  longer  find  the  phalanges  or  attempt  to  count  the 
bones.  They  become  irregular  polj'gons  or  trapezoids — less  like 
the  phalanges  than  the  radii  of  the  fins  of  a fish.  In  fishes  the  atite- 
rior  extremity  is  recognized  in  the  thoracic  fin ; and  we  may  even 
discover  the  prototypes  of  the  scapula  and  the  bones  of  the  arm.  I 
know  not  what  the  naturalist,  who  likes  to  note  tlie  gradual  decrease 
of  the  elementary  parts,  makes  of  these  hundred  bones  of  the  pad- 
dle or  of  the  fin  ; where  there  is  an  increase  of  the  number,  whiht, 
relatively  speaking,  there  is  a defect  of  form  and  motion,  of  the  parts. 


IN  THE  ICHTHYOSAURUS. 


85 


These  figures  are  taken  from  specimens  in  tlie  Col- 
lege of  Surgeons,  of  fossil  animals  of  singular  slruc- 
ture,  between  the  crocodile  and  the  fish.  They  are 
in  a calcareous  rock,  and  the  skeletons  are  entire,  but 
crushed,  and  a good  deal  disfigured.  Here  are  the 


extremities  or  paddles  consisting  of  a midtitude  of 
bones  articulated  ; and  among  these  we  still  discover 
the  humerus,  radius  and  ulna,  and  bones  of  the  car- 
pus and  fingers.  No  fault  is  to  be  found  with  the 
construction  of  these  instruments  ; they  are  suited  to 
their  offices,  and  no  bone  is  superfluous,  or  misplaced, 
or  imperfect.  The  ichthyosaurus  and  plesiosaurus 
(the  animals  which  offer  these  specimens)  inliabited 
the  sea  ; the  remains  are  found  low  in  the  lias  de- 
posit ; great  changes  have  been  wrought  on  the  land 
8 


86 


PECULIARITIES  IN  THE  HAND. 


and  on  the  deep  since  they  existed  ; and  the  race  of 
animals,  the  structure  of  whose  extremities  we  have 
been  engaged  in  examining,  were  not  then  in  being. 
When  we  discover  the  same  series  of  bones  in  the 
animals  of  the  old  world,  we  admit  the  existence  of 
the  same  system  ; and  we  must  necessarily  acknow- 
ledge the  progressive  developement  of  that  system, 
through  a period  of  time  incalculably  remote  ; even 
if,  instead  of  our  days  and  years,  referable  to  history, 
each  day  were  as  a thousand  years,  or  we  were  to 
make  our  estimate  by  the  records  of  the  revolutions 
which  have  left  their  traces  on  the  globe  itself. 

I have  now  given,  I hope,  sufficient  examples  of 
the  changes  in  the  bones  of  the  anterior  extremity, 
which  suit  them  to  every  possible  variety  of  use. 
After  a little  attention  to  the  form  of  the  human 
hand,  I shall  take  up  another  division  of  my  subject. 

The  motions  of  the  fingers  do  not  merely  result 
from  the  action  of  the  large  muscles  which  lie  on 
the  fore-arm — these  are  for  the  more  powerful  actions , 
but  in  the  palm  of  the  hand,  and  between  the  meta- 
carpal bones,  there  are  small  muscles  (Lumbricales 
and  Interossei),  which  perform  the  finer  motions,  ex- 
panding the  fingers  and  moving  them  in  every  direc- 
tion, with  great  quickness  and  delicacy.  These  are 
the  organs  which  give  the  hand  the  power  of  spin- 
ning, weaving,  engraving  ; and  as  they  produce  the 
quick  motions  of  the  musician’s  fingers,  they  are 
called  by  the  anatomist ^dfchiaZes.  Attention  to  our 
most  common  actions  will  shew  us,  how  the  dirfision 
into  fingers,  by -combining  motion  with  the  sense  of 
touch,  adapts  the  hand  to  grasp,  to  feel,  and  to  com- 
pare. We  shall  presently  see  how  well  the  points  of 
ihe  fingers  are  provided  for  feeling  : as  the  joints  and 
numerous  muscles  of  the  hand  are  adapted  for 
various,  distinct,  or  separate  motions. 

In  this  sketch  we  have  the  bones  of  the  paw  of  the 
adult  Chimpanzee,  from  Borneo ; and  the  remarka- 


PECULIARITIES  IN  THE  HAND. 


87 


ble  peculiarity  is  the  smallness  of  the  thumb ; it  ex- 
tends no  further  than  to  the  root  of  the  fingers.  On 
the  length,  strength,  free  lateral  motion,  and  perfect 
mobility  of  the  thumb,  depends  the  power  of  the 
human  hand.*  The  thumb  is  called  pollex,  because 
of  its  strength  ; and  that  strength  is  necessary  to  tlie 


power  of  the  hand,  being  equal  to  that  of  all  the 
fingers.  Without  the  fleshy  ball  of  the  thumb,  the 
power  of  the  fingers  would  avail  nothing  ; and,  ac- 
cordingly, the  large  ball,  formed  by  the  muscles  of 
the  thumb,  is  the  distinguishing  character  of  the 
human  hand,  and  especially  of  that  of  an  expert 
workman.! 

In  a French  book,  intended  to  teach  young  people 
philosoph}'",  the  pupil  asks  wdry  the  fingers  are  not  of 
equal  length  1 The  form  of  the  argument  reminds 
us  of  the  difficulty  of  putting  natural  questions — the 
fault  of  books  of  dialogue.  However,  the  master 
makes  the  scholar  grasp  a ball  of  ivory,  to  shew  him 
that  the  points  of  the  fingers  are  then  equal ! It 
would  have  been  better  had  he  closed  the  fingers 
upon  the  palm,  and  then  have  asked  whether  or  not 
they  corresponded.  This  difference  in  the  length  of 
the  fingers  serves  a thousand  purposes,  adapting  the 
hand  and  fingers,  as  in  holding  a rod,  a switch,  a 
sword,  a hammer,  a pen,  or  pencil,  engraving  tool, 
&c.,  in  all  Avhich,  a secure  hold  and  freedom  of 

* The  monkey  has  no  separate ^exor  long^ls  of  the  thumb.  Vicq. 
d’Azyr. 

t “ Manus  pan-a,  majori  adjutrix."  Albinos. 


88 


PECULIARITIES  IN  THE  HAND. 


motion  are  admirably  combined.  Nothing  is  more 
remarkable,  as  forming  a part  of  the  prospective 
design  to  prepare  an  instrument  fitted  for  the  various 
uses  of  the  human  hand,  than  the  manner  in  which 
the  delicate  and  moving  apparatus  of  the  palm  and 
fingers  is  guarded.  The  power  with  which  the  hand 
grasps,  as  when  a sailor  lays  hold  to  raise  his  body 
in  the  rigging,  would  be  too  great  for  the  texture  of 
mere  tendons,  nerves,  and  vessels ; they  would  be 
crushed,  Avere  not  every  part  that  bears  the  pressure, 
defended  with  a cushion  of  fat,  as  elastic  as  that  which 
we  have  described  in  the  foot  of  the  horse  and  the 
camel.  To  add  to  this  purely  passive  defence,  there 
is  a muscle  which  runs  across  the  palm  and  more 
especially  supports  the  cushion  on  its  inner  edge.  It 
is  this  muscle  Avhich,  raising  the  edge  of  the  palm, 
adapts  it  to  lave  water,  forming  the  cup  of  Diogenes. 

In  conclusion, — what  says  Ray, — “ Some  animals 
“ have  horns,  some  have  hoofs,  some  teeth,  some  ta- 
“ Ions,  some  claws,  some  spurs  and  beaks ; man  hath 
“ none  of  all  these,  but  is  Aveak  and  feeble,  and  sent 
“ unarmed  into  the  Avorld — Why,  a hand,  with  reason 
“ to  use  it,  supplies  the  use  of  all  these.” 


CHAPTER  IV. 


OF  THE  MUSCLES. 

The  muscle  of  the  body  is  that  fleshy  part,  with 
which  every  one  is  familiar.  It  consists  of  fibres 
which  lie  parallel  to  each  other.  This  fibrous,  or 
filamentous  part,  has  a living  endowment,  a power 
of  contraction  and  relaxation,  termed  irritability.  A 
single  muscle  is  formed  of  some  millions  of  these 
fibres  combined  together,  having  the  same  point  of 
attachment  or  origin,  and  concentrating  in  a rope  or 
tendon,  which  is  fixed  to  a moveable  part,  called  its 
insertion.  We  may  demonstrate  upwards  of  fifty 
muscles  of  the  arm  and  hand,  all  of  which  must  con- 
sent to  the  simplest  action  ; but  this  gives  an  imper- 
fect view  of  the  extent  of  the  relation  of  parts  which 
is  necessary  to  every  act  of  volition.  We  are  most 
sensible  of  this  combination  in  the  muscles,  when 
inflammation  has  seized  any  of  the  great  joints  of  the 
body  ; for  even  when  in  bed,  every  motion  of  an 
extremity  gives  pain,  through  the  necessity  of  a cor- 
responding movement  in  the  trunk.  When  we  stand, 
we  cannot  raise  or  extend  the  arm  without  a new 
position  of  the  body,  and  a poising  of  it,  through  the 
action  of  a hundred  muscles. 


ON  THE  ACTION  OF  THE  MUSCLES  OF  THE  ARM. 

We  shall  consider  this  subject  under  two  heads ; 
in  the  first,  we  shall  give  examples  of  the  living  pro- 
perty of  the  muscles  ; and  then  of  the  mechanical 
contrivances,  in  their  form  and  application.  In  all 

8* 


90 


OF  THE  MUSCLES  OF 


that  regards  the  muscles,  we  see  the  most  bountiful 
supply  of  power  commensurate  to  the  object,  but 
never  any  thing  in  the  least  degi'ee  superabundant. 
If  the  limb  is  to  be  moved  by  bringing  a muscle,  or  a 
set  of  muscles  into  action,  the  power  is  not  given  in 
that  excess  which  would  enable  them  to  overcome 
their  opponents  ; but  the  property  of  action  is  with- 
drawn from  the  opponents ; they  become  relaxed, 
and  the  muscles,  which  are  in  a state  of  contraction, 
perform  their  office  with  comparative  ease.  A sta- 
tionary condition  of  the  limb  results  from  a balanced 
but  regulated  action  of  all  the  muscles  ; which  con- 
dition may  be  called  their  tone.  If,  in  an  experiment, 
a weight  be  attached  to  the  tendon  of  an  extensor 
muscle,  it  will  draw  out  that  muscle  to  a certain 
degree,  until  its  tone  or  permanent  state  resists  the 
weight : but  if  the  flexor  muscle  be  now  excited,  this 
being  the  natural  opponent  of  the  extensor,  the 
weight  will  fall,  by  the  relaxation  of  the  extensor. 
So  that  the  motion  of  a limb  implies  an  active  state 
or  a change  in  both  classes  of  muscles,  the  one  to 
contract,  the  other  to  relax  ; and  the  will  influences 
both  classes.  Were  it  not  so  regulated,  instead  of 
the  natural,  easy,  and  elegant  motions  of  the  frame, 
the  attempt  at  action  would  exhibit  the  body  con- 
vulsed, or,  as  the  physicians  tenn  it,  in  clonic  spasms. 
The  similitude  of  the  two  sawyers,  mentioned  by 
Pale)g  gives  but  an  imperfect  idea  of  the  adjustment 
of  the  two  classes  of  muscles.  When  two  men  are 
sawing  a log  of  Avood,  they  pull  ahernateh',  and 
when  the  one  is  pulling,  the  other  resigns  all  exertion. 
But  this  is  not  the  condition  of  the  muscle.s — the 
relaxing  muscle  has  not  given  up  all  effort,  like  a 
loose  rope,  but  it  is  controlled  in  its  yielding,  with  as 
fine  a sense  of  adjustment,  as  is  the  action  of  the 
contracting  muscles.  Nothing  appears  to  us  more 
simple  than  raising  the  arm,  or  pointing  with  the 
finger  ; yet  in  that  single  act,  not  only  are  innume- 
rable muscles  put  into  activity,  but  as  many  are 


THE  ARM  AND  HAND. 


91 


thrown  out  of  action,  and  the  condition  of  these 
classes  is  totally  opposite  to  each  other,  under  the 
same  act  of  volition. 

By  such  considerations,  we  are  prepared  to  admire 
the  faculty  which  shall  combine  a hundred  muscles 
so  as  to  produce  a change  of  posture  or  action  of  the 
body  ; and  we  now  perceive  that  the  power  taken 
from  one  class  of  our  muscles,  may  be  considered  as 
if  it  were  bestowed  on  the  other ; so  that  the  pro- 
perty of  life,  wliich  we  call  the  irritability,  or  action 
of  a muscle,  is  upon  the  whole,  less  exhausted  than 
would  be  the  case  on  any  other  supposition. 

As  to  the  second  head,  our  demonstration  is  of  an 
easier  kind.  We  have  said  that  nature  bestows  abun- 
dantly, but  not  superfluously  ; a truth  evinced  in  the 
arrangement  of  the  muscles.  All  the  muscles  of  the 
limbs  have  their  fibres  running  in  an  oblique  direc- 
tion,— thus,  A.  being  the  tendinous  origin  of  a muscle, 
and  B.  the  tendinous  insertion,  the  fleshy  fibres  run 
obliquely  between  these  two  tendons. 


B 


The  fibre  acting  thus  obliquely  loses  power,  but 
gains  the  property  of  pulling  what  is  attached  to  its 
further  extremity  through  a greater  space,  while  it 
contracts.  This  mechairical  arrangement  is  intelli- 
gible on  the  law,  that  velocity  of  motion  through 
space,  is  equal  to  power  or  weight.  Here  in  the 
muscle,  there  is  a resignation  of  power  to  obtain  ve- 
locity of  motion. 

The  same  effect  is  produced  by  the  manner  in 
which  the  tendons  of  the  muscles  run  over  the  joints. 
They  would  act  more  powerfully,  if  they  went  in  a 


92 


OF  THE  MUSCLES  OF 


straight  line  to  the  toes  or  tips  of  the  fingers : but 
by  being  laced  down  in  sheaths,  they  move  the  toes 
and  fingers  with  a velocity  proportioned  to  their  loss 
of  power.  Let  us  see  how  far  this  corresponds  with 
other  mechanical  contrivances.  A certain  power  of 
wind  or  water  being  obtained,  the  machinery  is 
moved  ; but  it  is  desired  to  give  a blow,  with  a velo- 
city far  greater  than  the  motion  of  the  water  or  the 
turning  of  the  wheels.  For  this  purpose  a fly-wheel 
is  put  on,  the  spokes  of  which  may  be  considered  as 
long  levers.  The  wheel  moves  very  slowly,  at  first, 
but  being  once  in  motion,  each  impulse  accelerates  it 
with  more  and  more  facility  ; at  length,  it  acquires  a 
rapidity,  and  a centrifugal  force  which  nothing  can 
equal  in  its  effects,  but  the  explosion  of  gunpowder. 
The  mechanist  not  having  calculated  the  power  of 
the  accelerated  motion  in  a heavy  wheel,  has  seen 
his  machinery  split  and  burst  up,  and  the  walls  of 
the  house  blown  out  as  by  the  bursting  of  a bomb- 
shell. A bod}^  at  rest  receives  an  impulse  from  ano- 
ther, which  puts  it  into  motion — it  receives  a second 
blow  ; now,  this  second  blow  has  much  greater  effect 
than  the  first — foi’  the  power  of  the  first  was  ex- 
hausted in  changing  the  body  from  a state  of  rest  to 
that  of  motion — but  being  in  motion  when  it  receives 
the  second  blow,  the  whole  power  is  bestowed  on  the 
acceleration  of  its  motion  ; and  so  on,  b)*  the  third 
and  fourth  blows,  until  the  body  moves  with  a velo- 
city, equal  to  that  of  the  body  from  which  the  im- 
pulse is  originall)^  given.  The  slight  blovc  given  to 
a boy’s  hoop  is  sufficient  to  keep  it  running ; and  just 
so  the  fly-wheel  of  a machine  is  kept  in  rapid  action 
by  a succession  of  impulses,  each  of  which  would 
hardly  put  it  in  motion.  If  we  attempt  to  stop  the 
wheel,  it  will  give  a blow  in  which  a hundred  lesser 
impulses  are  combmed  and  multiplied. 

There  is,  in  the  machinery  of  the  animal  body,  in 
a lesser  degree,  the  same  interchange  of  velocity 
and  force.  When  a man  strikes  with  a hammer,  the 


THE  ARM  AND  HAND. 


93 


muscle  near  the  shoulder,*  c.  acts  upon  the  humerus, 
B.  in  raising  the  extended  lever  of  the  arm  and 
hammer,  with  every  possible  disadvantage  ; seeing 
that  it  is  inserted  or  attached  so  near  the  centre  of 
motion  in  the  shoulder  joint. 


But  the  loss  of  power  is  restored  in  another  form. 
What  the  muscle  d.  loses  by  the  mode  of  its  insertion, 
is  made  up  in  the  velocity  communicated  to  the  Isam- 
mer ; for  in  descending  through  a large  space,  it  ac- 
cumulates velocity,  and  velocity  is  equal  to  force. — 
The  advantage  of  the  rapid  descent  of  a heavy  body 
is,  that  a smart  blow  is  given,  and  an  effect  produced 
which  the  combined  power  of  all  the  muscles,  with- 
out this  mechanical  distribution  of  force,  could  not 
accomplish.  This  is,  in  truth,  similar  to  the  opera- 
tion of  the  fly  wheel,  by  which  tlie  gradual  motion  of 
an  engine  is  accumulated  in  a point  of  time,  and  a 
blow  is  struck  capable  of  crushing  or  of  stamping  a 
piece  of  gold  or  silver.  In  what  respect  does  the  me- 
chanism of  the  arm  differ  from  the  engine  with 
which  the  printer  throws  off  his  sheet  'I  Here  is  a 
lever  with  a heavy  ball  at  the  end  ; in  proportion  to 
its  weight,  it  is  difficult  to  be  put  in  motion.  The 

* A.  The  scapula,  or  shoulder  blade:  b.  the  humerus,  or  arm- 
bone  ; c.  the  deltoid  muscle  of  the  shoulder,  arising  from  the  shoulder- 
blade  and  clavicle,  and  inserted  into  the  arm-bone  ; d.  a muscle 
which  draws  the  arm  down,  as  in  striking  with  a sword  or  hammer. 


94 


MECHANICAL  PROPERTIES 


printer,  therefore,  takes  hold  of  the  lever  near  the  ball, 
at  A.  Were  he  to  continue  pulling  at  that  part  of 
the  lever,  he  would  give  to  the  ball  no  more  velocity 
than  that  of  his  hand  ; but  having  put  the  ball  into  mo- 
tion, he  slips  his  hand  down  the  lever  to  b.  He  could 


not  have  moved  the  weight,  had  he  applied  his  hand 
here  at  first ; but  it  being  now  in  motion,  the  whole 
strength  of  his  arm  is  given  to  the  lever  at  b.,  whilst 
the  velocity  of  the  great  weight  at  the  further  end  is 
accelerated.  Thus  the  weight  and  the  velocity  be- 
ing combined,  the  impulse  given  to  the  screw  is  much 
greater  than  if  he  had  continued  to  pull  upon  the 
further  end  of  the  lever  at  a. 

If  we  now  turn  our  eye  to  the  diagram  (page  93), 
we  sliall  understand  that  the  muscle  c.  raises  the 
long  lever  of  the  arm  at  a disadvantage,  or  ver}' 
slowly ; but  the  arm  being  moved,  that  motion  is 
rapidly  increased  by  each  successive  impulse  from 
the  muscle  ; and,  of  course,  the  velocity  of  the  further 
extremity  is  more  rapid  than  at  the  insertion  of  the 
tendon. 

Again,  if  we  consider  the  action  of  the  muscle  n. 
in  pulling  down  the  arm,  as  in  giving  a back  stroke 
with  the  sword,  we  have  the  combination  of  two  pow- 
ers,— weight  and  muscular  eflfort.  When  the  ham- 
mer descends,  the  rapidity  is  increased  by  the  mere 
effect  of  gra^•ity  ; but  when  the  action  of  the  muscle 


OF  THE  MUSCLES  OP  THE  ARM. 


is  conjoined,  the  two  forces,  progressively  increasing, 
greatly  augment  the  velocity  of  the  descent. 

The  same  interchange  of  power  for  velocity,  which 
takes  place  in  the  arm,  adapts  a man’s  hand  and 
fingers  to  a thousand  arts,  requiring  quick  or  lively 
motions.  The  fingers  of  a lady,  playing  on  the 
pianoforte,  or  the  compositor  with  his  types,  are 
instances  of  the  advantage  gained  by  this  sacrifice  of 
force  for  velocity  of  movement.  The  spring  of  the 
foot  and  toe  is  bestowed  in  the  same  manner,  and 
gives  elasticity  and  rapidity  in  running,  dancing,  and 
leaping. 

After  the  many  illustrations  from  mechanics  which 
we  have  olfered,  the  muscular  power  itself  must  be  a 
subject  of  surprise  and  admiration.  Gravity,  the 
running  of  water,  the  expansion  and  condensation  of 
steam,  the  production  of  gases,  the  spring  or  elasticity 
of  material,  or  all  these  combined,  could  not  have 
answered  the  varied  offices  performed  by  this  one 
property  of  life  possessed  by  the  muscles.  The  irri- 
table and  contractile  fibre,  matter  which,  chemically 
considered,  does  not  differ  from  the  fibrine  of  the 
blood,  being  endowed  with  this  property  of  contrac- 
tion, and  adapted  with  “ mechanical  ingenuity,” 
fulfils  a thousand  distinct  purposes,  in  volition, 
breathing,  speaking,  in  digestion,  assimilation,  circu- 
lation ; and  in  all  these  it  is  modified  to  the  wants 
and  condition  of  every  class  of  animals. 

From  what  the  reader  already  understands  of  the 
conformity  which  subsists  among  all  the  parts  of  an 
animal  body,  he  will  readily  comprehend  that  there 
is  a perfect  relation  between  the  bones  and  the  mus- 
cles : that  as  the  bones  change,  and  exhibit  a variety 
in  their  size,  relative  position,  and  articulations,  so 
there  is  an  adaptation  of  the  muscles.  We  sometimes 
find  them  separated  into  smaller  muscles,  and  some- 
times consolidated  into  more  powerful  masses. 

The  demonstration  to  the  anatomical  student  of  the 
muscles  of  the  human  hand  and  arm,  becomes  the 


96 


COMPARATIVE  ANATOMY 


test  of  liis  master’s  perfection  as  a teacher.  Nothing 
is  more  uninteresting,  tedious,  and  difficult  to  attend 
to,  than  the  demonstration  of  the  muscles  of  the  arm, 
when  they  are  taken  successively,  as  they  present 
themselves  ; but  when  they  are  taught  with  lucid 
arrangement,  according  to  the  motions  performed  by 
them,  it  is  positively  agreeable  to  find  how  much 
interest  may  be  given  to  the  subject. 

It  would  be  foreign  to  the  object  of  this  work  to 
introduce  such  demonstrations  here. 

Yet  it  is  very  remarkable  that  the  muscles  of  tlie 
arm  and  hand  should  resemble  so  closely  the  muscles 
of  the  fore  extremity  of  the  lion,  for  example.  Tlie 
flexors,  extensors,  pronators,  and  supinators  are,  in 
the  brute,  exactly  in  the  same  place,  and  bear  all  the 
relations  which  the  student  of  anatomy  is  taught  to 
observe  with  so  much  interest  in  the  human  arm. 
This  example  is  sufficient  to  show  how  accurately 
the  comparative  anatom)^  of  the  muscles  confonns  to 
that  of  the  bones  ; and  that  in  proportion  as  the  bones 
of  the  extremit)’  resemble  in  shape  and  power  of 
motion  those  of  the  human  arm,  so  do  the  muscles — 
another  proof  of  the  great  extent  of  the  system  of 
relations  established  in  the  animal  system. 

There  is  one  circumstance  more  which  should  not 
be  omitted  in  the  comparative  anatomy  of  these  mus- 
cles, as  it  exhibits  another  instance  of  confonnity  in 
their  structure,  to  the  offices  which  they  have  to  per- 
form. We  have  just  stated  that  the  power  of  con- 
traction is  a vital  property.  The  continued  action  of 
a muscle,  therefore,  exhausts  the  vitality  ; and  to 
support  that  action,  when  it  is  inordinate,  there  must 
be  a more  than  usual  provision  for  the  supply  of  this 
living  power,  viz  : — a means  of  increasing  or  perpetu- 
ating the  circulation  of  the  blood,  which  is  the  source 
of  all  vital  power. 

In  the  lemur  tardigradus  it  has  been  observed  that 
the  axillary  and  femoral  arteries,  the  great  arteries  of 
the  anterior  and  posterior  extremities,  have  this  pecu- 


OF  THE  JilUSCLES  OF  THE  ARM.  97 

iiarity — that  the  trunk  is  subdivided  into  a number 
of  equal-sized  cylinders,  which  again  unite  to  form  a 
single  trunk  previous  to  the  distribution  of  its  branches 
to  the  muscles.*  It  has  been  argued  that  this  pecu- 
liarity, as  it  produces  a retardation  of  the  blood,  is 
adapted  to  long  continued  action  in  the  muscles.  I 
believe  it  to  be  a provision  for  long  continued  action  ; 
because  the  animals  which  possess  it,  are  not  more 
remarkable  for  the  slowness  of  their  progression  than 
for  the  tenacity  of  their  hold.  The  extremities  are 
long  and  the  muscles  powerful,  either  to  sustain  the 
animal  by  grasping  the  branches  of  trees,  or  for  dig- 
ging ; but  surely  the  strength  of  the  muscles  cannot 
be  produced  by  retardation  of  the  circulation,  on  the 
principle,  universally  admitted,  that  the  expenditure 
of  arterial  blood  is  in  proportion  to  the  vital  force 
employed. 

Were  the  arteries  of  the  living  body  like  rigid 
tubes,  and  the  laws  of  the  circulation  the  same  as 
those  of  hydraulics,  such  might  be  the  conclusion. 
But  it  is  impossible  to  suppose  that  the  circulation  of 
the  blood  could  be  performed  according  to  the  laws 
which  govern  the  flow  of  water  in  dead  tubes.  The 
artery  is  dilatable,  it  contracts  with  a vital  force  ; both 
the  dilatabihty  and  the  contractility  of  arteries  are 
subject  to  the  influences  of  the  living  principle. 
When,  therefore,  the  artery  of  a limb  is  divided  into 
four  or  fiv'e  vessels,  the  result  is  a greater  capacity  of 
dilatation,  a greater  power  of  contraction  ; and  these 
being  vital  operations,  are  subject  to  be  influenced 
and  adjusted  according  to  the  necessity  for  the  in- 
crease or  diminution  of  the  circulation. 

If  such  a peculiarity  in  tiie  form  of  the  vessels  in 
the  extremities  of  these  animals,  retards  the  blood, 
it  can  only  be  during  repose  ; for,  on  excitement,  so 
far  from  retarding,  it  must  bestow  remarkable  power 
of  acceleration.  I conclude,  therefore,  that  this  va- 


* There  is  some  doubt  as  to  the  reunion  of  the  vessels. 
9 


98 


SUPERIORITY  OF  THE 


riety  of  distribution  in  the  arteries  is  a provision  for 
occasional  great  activity  in  the  muscles  of  the  limb, 
and  for  forcing  the  blood  into  contact  with  the  fibres, 
notwithstanding  their  continued  action  and  rigidity. 

We  have  seen  in  the  preceding  chapter  the  same 
organ,  which  moves  at  one  time  as  slowly  as  the 
hand  of  a watch,  at  another  moves  with  extreme 
rapidity  ; consequentlj%  we  cannot  admit  the  infer- 
ence that  the  tortuous  and  subdivided  artery  is  a pro- 
vision for  languid  motions. 

In  speaking  of  the  arteries  which  go  to  the  hand, 
it  may  be  expected  that  we  should  touch  on  a sub- 
ject, which  has  been  formerly  a good  deal  discussed, 
whether  the  properties  of  the  right  hand,  in  compa- 
rison with  those  of  the  left,  depend  on  the  course  of 
the  arteries  to  it.  It  is  aflSrmed  that  the  trunk  of 
the  artery  going  to  the  right  arm,  passes  off  from  the 
heart  so  as  to  admit  the  blood  directly  and  more 
forcibly  into  the  small  vessels  of  the  arm.  This  is 
assigning  a cause  Vi^hich  is  unequal  to  the  effect,  and 
presenting,  altogether,  too  confined  a view  of  the 
subject : it  is  a participation  in  the  common  error  of 
seeking  in  the  mechanism  the  cause  of  phenomena 
which  have  a deeper  source. 

For  the  conveniences  of  life,  and  to  make  us 
prompt  and  dexterous,  it  is  pretty  evident  that  there 
ought  to  be  no  hesitation  which  hand  is  to  be  used, 
or  which  foot  is  to  be  put  forward  ; nor  is  there,  in 
fact,  any  such  indecision.  Is  this  taught,  or  have 
we  this  readiness  given  to  us  by  nature  1 It  must 
be  observed,  at  the  same  time,  that  there  is  a distinc- 
tion in  the  whole  right  side  of  the  bod}',  and  that  the 
left  side  is  not  only  the  weaker,  in  regard  to  muscidar 
strength,  but  also  in  its  vital  or  constitutional  pro- 
perties. The  developement  of  the  organs  of  action 
and  motion  is  greatest  upon  the  right  side,  as  may  at 
any  time  be  ascertained  by  measurement,  or  the  tes- 
timony of  the  tailor  or  shoemaker ; certainly,  this 


RIGHT  HAND  OVER  THE  LEFT 


99 


superiority  may  be  said  to  result  from  the  more  fre- 
quent exertion  of  the  right  hand  ; but  the  pecu- 
liarity extends  to  the  constitution  also  ; and  disease 
attacks  the  left  extremities  more  frequently  than  the 
right.  In  opera  dancers,  we  may  see  that  the  most 
difficult  feats  are  performed  by  the  right  foot.  But 
their  preparatory  exercises  better  evince  the  natural 
weakness  of  the  left  limb,  since  these  performers  are 
made  to  give  double  practice  to  it,  in  order  to  avoid 
awkwardness  in  the  public  exhibition ; for  if  these 
exercises  be  neglected,  an  ungraceful  preference  will 
be  given  to  the  right  side.  In  walking  behind  a 
person,  it  is  very  seldom  that  we  see  an  equalized 
motion  of  the  body  ; and  if  we  look  to  the  left  foot, 
we  shall  find  that  the  tread  is  not  so  firm  upon  it, 
that  the  toe  is  not  so  much  turned  out  as  in  the  right, 
and  that  a greater  push  is  made  with  it.  From  the 
peculiar  form  of  woman,  and  the  elasticity  of  her 
step  resulting  more  from  the  motion  of  the  ankle 
than  of  the  haunches,  the  defect  of  the  left  foot  when 
it  exists,  is  more  apparent  in  her  gait.  No  boy  hops 
upon  his  left  foot,  unless  he  be  left  handed.  The 
horseman  puts  the  left  foot  in  the  stirrup  and  springs 
from  the  right.  We  think  we  may  conclude,  that 
every  thing  being  adapted  in  the  conveniences  of 
life  to  the  right  hand,  as  for  example  the  direction  of 
the  worm  of  the  screw  or  of  the  cutting  end  of  the 
auger,  is  not  arbitrary,  but  is  related  to  a natural  en- 
dowment of  the  body.  He  who  is  left  handed  is 
most  sensible  to  the  advantages  of  this  adaptation, 
from  the  opening  of  the  parlour-door  to  the  opening 
of  a pen-knife.  On  the  whole,  the  preference  of  the 
right  hand  is  not  the  effect  of  habit,  but  is  a natural 
provision,  and  is  bestowed  for  a very  obvious  pur- 
pose : and  the  property  does  not  depend  on  the  pecu- 
liar distribution  of  the  arteries  of  the  arm — but  the 
preference  is  given  to  the  right  foot,  as  well  as  to  the 
right  hand. 


CHAPTER  V. 


f *' 


/ I 
* » 


THE  SUBSTITUTION  OF  OTHER  ORGANS  FOR  THE  HAND. 

After  having  examined  the  manner  in  which  one 
instrument,  the  hand,  is  modified  and  adapted  to  a 
variety  of  purposes  in  different  animals,  there  re- 
mains only  this  mode  of  elucidation — that  we  con- 
trast it  with  its  imperfect  substitutes  in  other  creatures. 
I might,  indeed,  have  shewn  in  the  insect  tribes  the 
most  curious  examples  of  instruments  for  similar  pur- 
poses with  the  hand  and  fingers  of  man  ; but  I have 
intentionally  confined  this  incpiiry  to  the  liigher  class- 
es of  animals. 

The  habits  of  some  fishes  reciuire  that  they  should 
cling  firndy  to  the  rocks  or  to  whatever  presents  to 
them.  There  locomotive  powers  are  perfect ; but 
how  are  they  to  become  stationary  in  the  tide  or  the 
stream'?  I have  often  tliought  it  wontlerful  that  the 
salmon  or  the  trout,  for  example,  should  keep  its 
place,  night  and  day,  in  the  rapid  current.  In  the 
sea,  there  are  some  fishes  especially  provided  with 
means  of  clinging  to  the  rocks.  The  lumpfish,  cy- 
clopterus  lumpus,  fastens  itself  by  an  apparatus  which 
is  on  the  lower  part  of  its  body.  The  sucking  fish, 
remora,  has  a similar  provision  on  its  back.  It  at- 
taches itself  to  the  surface  of  the  shark  and  to  what- 
ever is  afloat ; and,  of  course,  to  the  bottoms  of  ships. 
The  ancients  believed  it  capable  of  stopping  a ship 
under  sail,  and  Pliny,  therefore,  called  it  remora. 
We  must  admire  the  means  b)^  which  these  fishes 
retain  their  proper  position  in  the  water,  without 
clinging  by  their  fins  or  teeth,  and  while  they  are 


SUBSTITUTES  FOR  THE  HAND. 


101 


free  for  such  efforts  as  enable  them*  to  seize  their 
food.  The  apparatus  by  which  they  attach  them- 
selves resembles  a boy’s  sucker  : the  organ  being 
pressed  against  the  surface  to  which  the  creature  is 
to  be  fixed,  the  centre  is  drawn  by  muscles  in  the 
same  manner  that  the  sucker  is  drawn  with  the  cord, 
and  thus  a vacuum  is  made. 

In  the  cuttle-fish  we  see  a modification  of  this 
apparatus ; the  suckers  are  on  the  extremities  of  their 
processes  or  arms,  and  become  instruments  of  prehen- 
sion and  of  locomotion.  They  are  capable  of  turning 
in  all  directions,  either  to  fix  the  animal  or  to  drag  it 
from  place  to  place.  In  the  Indian  Seas,  these  crea- 
tures become  truly  terrific  from  the  length  of  their 
arms,  which  extend  to  eight  or  nine  fathoms,  and 
from  the  firmness  with  which  they  cling. 

Dr.  Shaw  tells  us,  that  on  throwing  a fish  of  the 
species  cyclopterus  lumpus  into  a pail  of  water,  it 
fixed  itself  so  firmly  to  the  bottom,  that  by  taking 
hold  of  the  tail,  he  lifted  up  the  pail,  although  it  con- 
tained some  gallons  of  water. 

There  is  another  fish,  which  from  its  name  we 
should  expect  to  perform  strange  antics  ; it  is  called 
harlequin  angler. f It  appearance  is  grotesque  and 

singular  ; the  pectoral  fins  resemble  short  arms,  and 
are  palmated  at  their  tips.:^  M.  Renau,  in  his  histo- 

* In  the  Mollusca  and  Zoophytes  we  find  many  instances  of  the 
animal  holding  on  against  the  force  of  tide  or  current.  The  Actiniae 
fix  themselves  to  rocks  and  shells ; and  some,  as  the  sea  carnation, 
hang  suspended  from  the  lower  surface  of  projecting  rocks,  resem- 
bling the  calyx  of  a flower.  By  the  elongation  of  their  tentacula,  they 
expand  and  blow  out  like  a flower;  but  instead  of  petals,  these  are 
prehensile  instruments  by  which  they  draw  whatever  food  floats 
near  them  into  their  stomachs.  The  Byssus  of  the  muscle  is  a set  of 
filaments  which  retains  the  shell  at  anchor  and  prevents  it  drifting  or 
rolling  with  the  tide.  These  filaments  are  the  secretion  of  a gland, 
and  whilst  they  are  fixed  to  the  rock,  the  gland  retains  the  hold  at 
their  other  ends.  The  shell  of  the  oyster  is  itself  cemented  to  the  rock. 

t Lophius  Histrio,  from  a Greek  word  that  has  reference  to  the 
process  which  floats  from  the  head,  like  a streamer  or  pennant. 

J These  fins  have  two  bones  in  them  like  the  radius  and  ulna ; but 
Cuvier  says,  that  they  are  more  strictly  bones  of  the  carpus. 


102 


SUBSTITUTES  FOR  THE  HAND. 


ly  of  fishes,  affirms  that  he  knew  an  individual  of  this 
species  ; and  the  expression  is  not  so  incorrect,  since 
he  saw  it  for  three  days  out  of  the  water,  walking- 
about  the  house  in  the  manner  of  a dog-.  The  cir- 
cumstance of  its  walking  out  of  the  water  has  some 
interest,  as  showing  relations  between  organs  which 
are  apparently  the  least  connected.  The  fact  of  this 
fish  living  out  of  the  water  is  doubted  ; but  the  form 
of  its  branchial  organs  inclines  me  to  believe  it ; and 
its  habits  require  such  a provision.  In  this  genus, 
the  operculum  does  not  open  to  let  the  respired  water 
pass  off  freely  behind,  as  in  most  fishes ; but  the  water 
is  discharged  by  a small  aperture  which,  in  Mr. 
Owen’s  opinion,  is  capable  of  being  closed  bj*  a 
sphincter.  The  cavities  in  which  the  branchiae  lie 
are  large,  and  this  is,  indeed,  partly  the  reason  of  the 
monstrous  head  of  this  fish.  Thus,  it  has  not  only 
its  fins  converted  into  feet,  Irut  its  gills  into  pouches, 
capable  of  containing  water,  and  of  pennitting  the 
function  of  the  branchiae  to  proceed  when  the  water  is 
retired  ; that  is,  when  it  lies  in  mud,  or  shallow 
pools  ; for  in  such  situations  does  the  lophius  find  its 
food,  where  it  angles  for  it  in  a very  curious  maimer. 

But  there  are  other  fishes  that  move  out  of  the 
water  on  dry  land,  and  even  ascend  trees,  without 
being  carried  there  by  floods.  The  'perca  scandens, 
by  means  of  the  spines  of  its  gill-covers,  and  the 
spinous  raj's  of  its  fins,  climbs  trees  ; so  that  Dr. 
Shaw  calls  it  the  climbing  fish.* 

All  creatures  which  have  their  skins  protected, 
whether  b}^  feathers,  or  shells,  or  scales,  have  an 
exquisite  touch  in  their  mouth,  or  in  the  appendages 
which  hang  from  it.  Fishes  have  cim  which  hang 
fiom  their  mouth,  and  these  are  equivalent  to  the 
palpa  and  tentacula  of  insects  and  Crustacea.  The 

* The  spines  of  the  Echinus  are  moveable  ; they  assist  in  progres- 
sion. Tliey  are  directed  towards  an  advancing  enemy  ! Although 
these  spines  may  be  effectual  for  their  purpose  tliej’  are  the  lowest  or 
least  perfect  substitutes  for  the  e.xttomities. 


SUBSTITUTES  FOR  THE  HAND. 


lOS 


fishing  lines  of  the  lophius  piscatorius  are  examples  of 
these  processes  : and  Pliny  relates  that  this  frog-like 
fish,  hiding  in  the  mud,  leaves  the  extremities  of 
these  filaments  visible ; which,  from  their  resem- 
blance to  worms,  entice  the  smaller  fishes,  and  they 
become  the  prey  of  their  concealed  enemy.  It  is 
surprising  how  varied  the  means  are  by  which  fishes 
obtain  their  food.  The  chottodon  (bandouliere  a bee) 
squirts  water  at  flies  as  they  pass  and  brings  them 
down.  The  scimna  jaculatnx,  according  to  Pallas, 
has  a similar  power  ; and  the  spams  insidiator  catch- 
es aquatic  insects  by  the  sudden  projection  of  its 
snout.  It  is  affirmed  by  some  naturalists  that  the 
rays  of  the  dorsal  and  anal  fins,  as  in  the  cordonnier 
of  Martinique,  zeus  ciliaris,  le  blepharis,  Cuv.,  are 
employed  to  grapple  or  coil  round  the  stems  of  plants 
and  sustain  the  fish. 

The  several  offices  attributed  to  these  processes  in 
fishes  imply  that  they  possess  sensibilit  if  not  mus- 
cular power. 

By  anatomical  investigation  and  experiment,  I, 
some  years  ago,  discovered  that  the  sensibility  of  all  the 
head  and  of  its  various  appendages  resulted  from  one 
nerve  only  of  the  ten  which  are  enumerated  as  aris- 
ing from  the  brain,  and  are  distributed  within  and 
around  the  head  ; and,  pursuing  the  subject  by  the 
aid  of  comparative  anatom}^  1 found  that  a nerve  cor- 
responding to  this,  which  is  the  fifth  nerve  in  man, 
served  a similar  purpose  in  all  the  lower  animals.  In 
creatures  which  are  covered  with  feathers  oi'  scales, 
or  protected  by  shell,  this  nerve  becomes  almost  the 
sole  organ  of  sensibility.  It  is  the  developement  of 
this  nerve  which  gives  sensibility  to  the  cirri,  which 
hang  about  the  mouths  of  fishes,  and  to  the  palpa  of 
the  Crustacea  and  insects.  It  is  the  same  nerve 
which  supplies  the  tongue,  and  is  the  organ  of  its  ex- 
quisite sensibility  to  touch,  as  well  as  of  taste.  In 
some  animals,  especiall)^  in  the  reptiles,  the  tongue, 
by  its  length  and  mobility,  becomes  a substitute  foi 


104 


SUBSTITUTES  FOR  THE  HAND. 


these  external  appendages.  We  might  have  noticed 
before,  that  the  tongue  is  an  organ  of  prehension  as 
well  as  of  touch.  With  it  the  ox  gathers  in  the  her- 
bage ; and  in  the  giraffe,  it  is  rather  curious  to  observe 
that  as  the  whole  frame  of  the  animal  is  calculated 
to  raise  the  head  to  a great  height,  so  is  the  tongue 
capable  of  projecting  beyond  the  mouth  to  an  extra- 
ordinary extent,  to  wrap  round  and  pull  do'Rui  the  ex- 
treme branches  of  trees.  The  whiskers  of  the  feline 
quadrupeds  possess  a fine  sensibility  through  branches 
of  the  fifth  nerve,  which  enter  their  roots.  Birds 
have  a high  degree  of  sensibility  to  touch  in  their 
mouths.  In  ducks,  and  all  that  quaffer  with  their 
bills  under  water,  the  sense  is  very  fine,  and  we  find, 
on  dissection,  that  a branch  of  the  fifth  nerve,  remark- 
ably developed,  is  distributed  on  the  upper  mandible. 
Animals  feel  in  the  whole  of  their  external  surface  ; 
and  we  may  say  that  serpents,  by  coiling  themselves 
round  a body,  have  the  organ  of  touch  all  over  them. 
Still  the  fifth  pair  of  nerves  in  the  head,  or  the  nerve 
analogous  to  it,  is  the  main  instrument  of  touch  in  the 
greater  number  of  animals  where  extremities  are  want- 
ing. There  are  organs  varying  in  their  conformation, 
sometimes  delicate  palpa,  sometimes  horny  rods,  and 
these  are  often  possessed  of  muscularity  as  well  as 
sensibility;  but  to  all,  the  sense  of  touch  is  bestowed 
through  a nerve  corresponding  with  the  fifth  pair,  the 
nerve  of  the  tongue  and  lips,  and  of  the  muscles  of  the 
jaws  in  man. 

But  we  may  repeat,  that,  necessary  as  these  appen- 
dages and  this  sensibility  are  to  the  existence  of  these 
animals,  their  imperfections  serve,  by  contrast,  to 
show  how  happily  the  different  properties  are  com- 
bined in  the  hand  ; in  which  we  perceive  the  sensi- 
bilities to  changes  of  temperature,  to  touch,  and  to 
motion,  united  with  a facility  in  the  joints  of  unfold- 
ing and  moving  in  every  possible  degree  and  direc- 
tion, without  abruptness  or  angularity,  and  in  a man- 
ner inimitable  by  any  artifice  of  joints  and  levers. 


CHAPTER  VI. 


THE  ARGUMENT  PURSUED  FROM  THE  COMPARATIVE 
ANATOMY. 

So  far  as  we  liave  hitherto  proceeded,  by  examin- 
ing objects  in  comparative  anatomy  which  from  their 
magnitude  can  not  be  misunderstood,  we  have  been 
led  to  conclude  that,  independently  of  the  system  of 
parts  marvellously  combined  to  form  the  individual 
animal,  there  is  another,  more  comprehensive  system, 
which  embraces  all  animals  ; and  which  exhibits  a 
certain  uniformity  in  the  functions  of  life,  however 
different  in  form  or  bulk  the  creatures  may  be,  or  to 
Avhatever  condition  of  the  globe  they  ma}'-  have  been 
adapted.  We  have  seen  no  accidental  deAuation  or 
deformity,  but  that  every  change  has  been  for  a pur- 
purpose,  and  every  part  has  had  its  just  relation. 
We  have  AAutnessed  all  the  varieties  moulded  to  such 
a perfect  accommodation,  and  the  alterations  pro- 
duced by  such  minute  degrees,  that  all  notion  of  ex- 
ternal and  accidental  agency  must  be  rejected. 

We  might  carry  our  demonstration  doAvmAvard 
through  the  loAver  classes  of  animals  ; for  example, 
Ave  might  trace  the  feet  of  insects  from  their  most 
perfect  or  complex  state,  till  they  disappear  ; or,  ob- 
serving the  changes  in  another  direction,  we  might 
folloAv  out  the  same  parts  from  the  smallest  begin- 
ning to  the  most  perfect  condition  of  the  member, 
Avhere  Ave  see  the  thigh,  leg,  and  tarsus  of  the  fly. 
We  might  distinguish  them  at  first  as  the  fine  cirri, 
like  minute  bristles,  Avhich  on  the  bodies  of  AAmrms 
take  slight  hold  of  the  surface  over  AAdiich  they  creep. 
In  the  sea  mouse,  [aphrodita)  Ave  might  notice  these 


106 


THEORY  OF 


bristles  standing  out  from  distinct  mamraillaiy  pro- 
cesses, which  are  furnished  with  appropriate  muscles. 
Then  in  the  myriapodes,  the  first  order  of  insects,  Ave 
might  see  the  same  “ many  feet,”  and  each  foot 
having  a distinct  articulation.  From  that,  we  might 
pass  to  the  feet  of  those  insects,  where  there  is  a thigh, 
leg,  and  foot,  Avith  the  most  perfect  system  of  flexors, 
extensors,  and  adductor  muscles,  possessing,  in  fine, 
all  that  Ave  most  admire  in  the  human  anatomy. 
Nay,  it  is  most  curious  to  observe  hoAV  the  feet  of  the 
true  insects  are  again  changed  or  modified ; taking 
neAV  offices,  the  anterior  feet  becoming  feelers,  organs 
of  prehension,  or  hands.  When,  AAuth  such  an  ob- 
ject, Ave  vieAV  the  delicate  and  curiously  adapted  in- 
struments of  insects,  we  must  perceive  that  it  AA’ould 
be  easy  to  trace  almost  eA'ery  part  through  a succes- 
sion of  modifications.  Among  the  vertebrata,  Ave  have 
seen  the  hand  become  a Aving  or  a fin  ; so  might  AA’e 
trace  the  Avings  of  insects.  If  we  begin  with  a fl}', 
Avhich  has  two  delicate  and  perfect  Avings  incased 
and  protected,  we  find  that  the  coA'ers  are  raised  to 
admit  the  expansion  of  the  AAungs.  In  another,  the 
case  becomes  a wing ; and  the  fly  is  characterized 
by  four  Avings.  Proceed  to  examine  a third  example, 
and  Ave  shall  discover  that  this  anterior  Aving  is  larger 
and  more  perfect  than  the  posterior  ; the  fourth  spe- 
cimen has  lost  the  posterior  AAungs,  and  has  onh'  two 
perfect  ones  ; and  if  Ave  continue  the  examination, 
the  next  specimen  will  present  an  insect  depriA'ed  of 
Avings  altogether.  These  are  not  freaks  of  nature, 
but  neAV  forms  of  the  body ; neAA'  appendages  re- 
quii’ed  for  a different  poising  of  the  fly  in  its  flight. 
They  are  adaptations  in  that  regular  series  Avhich 
AA^e  have  observed  to  obtain  in  the  larger  animals, 
and  Avhere  the  intention  can  not  be  mistaken. 
A A^ery  natural  question  Avill  force  itself  upon  us,  hoAv 
are  those  varieties  to  be  explained  7 

The  curious  adaptation  of  a member  to  different 
offices  and  to  different  conditions  of  the  animal  has 


ELEMENTAL  PARTS. 


107 


led  to  a very  extraordinary  opinion  in  the  present 
day, — that  all  animals  consist  of  the  same  elements. 
It  would  be  just  to  say  that  they  consist  of  the  same 
chemical  elements,  and  that  they  attract  and  assimi- 
late matter  by  the  performance  of  the  same  vital 
functions,  through  every  species  of  animals,  however 
different  in  form  and  structure.  But  by  the  elements 
which  are  now  mentioned,  the  authors  of  this  new 
theory  mean  certain  pieces  which  enter  into  the 
structure  of  the  body,  and  which  they  illustrate  by 
the  analogy  of  the  building  materials  of  a house. 
If  these  materials,  they  say,  are  exhausted  in  the  or- 
namental parts  of  the  portico  and  vestibule,  there 
must  be  a proportionate  limitation  of  the  apartments 
for  the  family  ! 

This  new  theory  has  been  brought  forward  with 
the  highest  pretensions ; the  authors  of  it  have  called 
upon  us  to  mark  tlie  moment  of  its  conception  as  the 
commencement  of  a new  eera  ! Tiiey  speak  of  the 
“elective  affinities  of  organs,”  “the  balancing  of  or- 
gans,” “ a new  principle  of  connection,”  and  a “ new 
theory  of  analysis.” — The  hypothesis  essentially  is 
this,  that  when  a part,  which  belongs  to  one  animal, 
is  missed  in  another,  we  aie  to  seek  for  it  in  some 
neighbouring  organ : and  on  such  grounds  they  af- 
firm, that  this  surpasses  all  former  systems  as  a 
means  of  discovery.  Now,  the  perfection  or  aggran- 
dizement of  any  one  organ  of  an  animal  is  not  at- 
tended with  the  curtailment  or  proportional  deficien- 
cy of  any  other.  Like  ourselves,  perhaps,  the  sup- 
porters of  this  theory  dwell  too  much  upon  the  bones  ; 
but  even  in  them,  we  shall  show  that  the  system  is 
untenable.  In  the  mean  time,  we  may  ask,  do  ad- 
ditional parts  connected  with  the  stomach,  making  it 
highly  complex,  as  in  ruminating  animals,  shorten 
the  intestinal  canal,  or  make  its  form  simpler  1 On 
the  contrary,  is  not  a complex  stomach  necessarily 
connected  with  a long  and  complicated  intestine  ? — 
Does  a complex  intestinal  canal  throughout  all  its 


108 


THEORY  OF 


course  render  imperfect  the  solid  viscera  which  are 
in  juxtaposition  to  itl  Is  there  any  defect  in  them, 
because  the  organs  of  digestion  are  perfect,  or  com- 
plicated'? Does  the  complex  heart  imply  a more 
simple,  or  a more  perfect  condition  of  the  lungs  ? In 
short,  as  animals  rise  in  the  scale  of  existence,  do  we 
not  find  that  the  systems  of  digestion,  circulation,  re- 
spiration and  sensation,  bear  ever  a proportional  in- 
crease ? Is  there  any  instance  of  an  improvement  in 
one  organ  thrusting  another  out  of  its  place,  or  di- 
mi  nisliing  its  volume'? 

Now,  as  to  the  osseous  system,  were  we  to  follow 
these  theorists  into  the  very  stronghold  of  their  posi- 
tion, the  bones  of  the  skull,  where  the  real  intricacy 
of  the  parts  allows  them  some  scope  for  their  ingenu- 
ity, vce  might  show  how  untenable  the  principle  is 
which  they  assume.  But  we  must  confine  ourselves 
to  our  own  subject. 

In  the  higher  orders  of  the  vertebi  ata,  we  find  that 
the  bones  of  the  shoulder  perform  a double  office  ; 
that  they  have  an  important  share  in  the  act  of  re- 
spiration, whilst  they  are  perfect  as  a foundation  for 
the  extremity.  Now,  let  us  take  an  instance  where 
the  mode  of  respiration  of  the  animal  is  inconsistent 
with  what  we  ma}'^  term  the  original  mechanism  of 
the  bones  of  the  shoulder.  In  the  batrachian  order, 
tlie  ribs  are  wanting : where  then  are  we  to  look  for 
them?  Shall  we  follow  a system  which  informs  us 
that  when  a bone  is  wantuig  in  the  cavity  of  the  ear, 
we  are  to  seek  for  it  in  the  jaw  ; and  which,  yet,  shall 
leave  us  in  the  contemplation  of  this  class  of  ani- 
mals deficient  in  thirty-two  ribs,  without  pointing  out 
where  they  are  to  be  found,  or  how'  their  elements  are 
built  up  in  other  structures  ? If,  on  the  contrary, 
we  take  the  principle  that  parts  are  formed  or  with- 
drawn, with  a never-failing  relation  to  the  function 
which  is  to  be  performed,  we  see  that  no  sooner  are 
the  compages  of  the  chest  removed,  and  the  should- 
er thus  deprived  of  support,  than  the  bones  to  which 


ELEMENTAL  PARTS. 


109 


the  extremity  is  fixed  are  expanded  and  varied,  both 
in  form  and  articulation,  so  as  to  fulfil  their  ma^in  ob- 
ject  of  giving  security  and  motion  to  the  arm. 

With  respect  to  the  instance  which  we  have  acci- 
dentally noticed  regarding  the  mechanism  of  tire  jaw 
ill  birds,  and  which  is  brought  forward  so  vauntingl}" 
as  a proof  of  the  excellence  of  the  theory,  it  does, 
indeed,  prove  the  reverse  of  what  is  assumed.  The 
only  effect  of  this  hypothesis  is  to  make  us  lose  sight 
of  the  principle  which  ought  to  direct  us  in  the  obser- 
vation of  such  curious  structures,  as  well  as  of  the 
conclusions  to  which  an  unbiassed  mind  would  come. 
The  matter  to  be  explained  is  simply  this  : — the 
chain  of  bones  in  the  ear,  which  is  so  curiously 
adapted  in  the  mammalia  to  convey  the  vibrations  of 
the  membrane  of  the  tympanum  to  the  nerve  of 
hearing,  is  not  found  in  the  organ  of  hearing  hi 
birds  ; but  there  is  substituted  a mechanism  entirely 
different.  They  choose  to  say  that  the  incus,  one  of 
the  bones  of  the  chain,  is  wanting  in  the  bird. 
Where  shall  we  find  it  ? — ^they  ask.  Here  it  is  in 
the  apparatus  of  the  jaw  or  mandible  ; in  that  bone 
which  is  called  os  quadratum.  1 believe  that  the 
slight  and  accidental  resemblance  which  this  bone 
(b.)  in  the  bird  has  to  the  incus,  is  the  real  origin  of 
this  fancy.  Let  us  follow  a juster  mode  of  reasoning, 
and  see  how  this  hypothesis  obscures  the  beauty  of 
the  subject.  The  first  step  of  the  investigation 
ought  to  be  to  inquire  into  the  fact,  if  there  be  any 
imperfection  in  tlie  hearing  of  birds.  That  is  easily- 
answered — the  hearing  of  birds  is  most  acute  ; the 
slightest  noise  alarms  ; and  the  nightingale,  or  other 
bird  of  song,  in  a summer  evening,  will  answer  to 
the  note  of  his  rival  when  he  is  out  of  our  hearing. 
We  have  next  to  observe  tlie  imperfection  in  the 
organ — the  want  of  an  external  ear ; which,  w^ere  it 
present,  would  be  at  variance  with  all  that  we  have 
most  to  admire  in  the  shape  of  the  bird  and  the  di lec- 
tion of  the  feathers,  as  conducing  to  its  rapid  passage 
10 


110 


THEORY  OF 


through  the  air.  With  this  obvious  defect  of  the 
external  ear,  can  we  admit  that  the  internal  ear  is 
also  imperfect,  notwithstanding  the  very  remarkable 
acuteness  of  hearing,  which  we  know  to  result  from 
this  internal  structure,  and  from  it  alone  1 Now  we 
do,  in  fact,  find  a different  structure  in  the  ear  of 
birds  ; but,  yet  nothing  is  wanting.  The  columella 
is  a shaft  of  bone  of  exquisite  delicacy,  which  is 
extended  from  the  outward  membrane  of  the  ear  to 
the  labyrinth  or  proper  seat  of  the  nerve  of  hearing. 
It  occupies  the  place  and  office  of  the  chain  of  four 
bones  which  belong  to  the  ear  of  mammalia.  We 
have  no  authority,  however,  for  affirming  that  the 
incus  is  here  wanting  moie  than  an}^  other  bone  of 
the  chain ; — and  if  it  be  said  that  the  os  quadratum 
is  the  missing  incus,  why  should  not  we  find  in  the 
oviparous  reptiles,  where  there  is  a columella  in  the 
ear,  an  os  quadratum  in  the  jawl 

From  this  mode  of  inquiry,  we  find  that  the  sense 
of  hearing  is  enjoyed  in  an  exquisite  degree  in  birds  : 
that  the  organ  of  the  sense  is  not  imperfect,  but  is 
adapted  to  a new  construction,  and  a varied  appara- 
tus— suited  to  the  condition  of  the  bird : and  that 
there  is  no  accidental  dislocation  or  substitution  of 
something  less  perfect  than  what  we  find  in  other 
classes  of  animals. 

If  we  now  look  to  the  struc  ture  of  the  mandible  of 
the  bird,  we  shall  find  as  curious,  though  a some- 
what grosser  example  of  mechanical  relation.  The 
bill  of  the  bird,  in  some  degree,  pertains  to  our  sub- 
ject, as  it  is  the  organ  of  prehension  and  of  touch. 
It  is  withal  a fly  trap — hence,  its  motions  must  be 
rapid  : and  the  velocity  is  increased  by  the  most 
obvious  means  imaginable, — that  is,  by  givingmotion 
to  both  mandibles,  instead  of  to  one.  When  a dog 
snaps  he  throws  back  his  head,  and  thereby  raises 
the  upper  jaw  at  the  same  time  that  the  lower  jaw  is 
dropped ; but  these  are  slow  and  clumsy  motions, 
pertaining  to  the  muscles  of  the  neck  as  well  as  of 


ELEMENTAL  PARTS. 


Ill 


the  jaws,  and  the  poor  hound  makes  man)^  attempts, 
Irefore  he  catches  the  fly  that  teazes  him.  But  a 
swallow  or  fly-catcher  makes  no  second  effort,  so 
admirably  suited  is  the  apparatus  of  prehension  to  the 
liveliness  of  the  eye  and  the  instinct.  The  adaptation 
of  the  instrument  consists  in  this,  that  the  muscles 
which  open  the  lower  mandible,  by  the  same  effort, 


J3 


open  the  upper  one  : a.  is  a process  of  the  lower 
mandible,  projecting  much  behind  the  centre  of  mo- 
tion, and  the  muscle  which  is  attached  to  it  opens 
the  bill but  at  the  same  time,  the  lower  mandible 
presses  upon  the  bone  b.,  the  os  quadratum : now, 
there  is  attached  to  this  bone,  projecting  forwards, 
with  its  anterior  extremity  fixed  against  the  upper 
mandible,  a shaft  or  process  of  bone  c.  ; and  this 
receives  the  pressure  of  the  os  quadratum,  when  the 
muscle  acts  ; so  that  being  thrust  forwards,  like  a 
bolt,  it  opens  the  upper  mandible,  which  moves  upon 
the  skull  at  d.  Here,  then,  is  a piece  of  mechanism 
as  distinct  as  the  lock  of  a gun,  which  is  for  the  pur- 
pose, as  we  have  said,  of  giving  rapidity  to  the 
motions  of  the  bill.  Is  it  nearer  the  truth  to  consi- 
der this  as  a new  apparatus,  suiting  the  necessities  of 
the  creature,  or  an  accidental  result  of  the  introduc- 
tion of  a bone,  which  in  its  proper  office  has  nothing 
to  do  with  the  jawl 


112 


THEORY  OF  THE 


But  we  have  wandered  somewhat  from  our  sub- 
ject.. We  liave  taken  the  bones  of  the  shoulder,  or 
those  of  the  extremity  which  are  nearest  to  the 
trunk ; we  may  pursue  the  inquiry  by  noticing  those 
which  are  most  remote  from  it.  In  the  bones  of  the 
hand,  we  have  seen  that  the  same  system  was  va- 
riously modified  so  as  to  be  adapted  to  every  possible 
change  in  office.  But  as  it  is  insisted  that  the  num- 
ber of  parts  continue  the  same,  what  can  we  say  to 
the  bones  of  the  paddle  in  the  saurian  and  chelonian 
tribes,  which,  as  in  the  ichthyosaurus  for  example, 
consist  of  sixty  or  seventy  polygonous  bones  ; whilst 
in  the  horse  there  are  only  fifteen  bones  ; and  in 
man,  twentj-seven.  Yet,  with  all  those  bones  in 
the  paddle,  there  is  still  the  full  complement  in  the 
part  that  corresponds  with  the  arm.  If  the  sr^stem 
fail  us  in  such  an  obvious  instance  as  this,  with  what 
confidence  can  we  prosecute  the  intricate  bones  of 
the  spine  and  head  under  its  guidance  1 

Seeking  assistance  from  the  works  of  distinguished 
naturalists,  we  do  not  always  find  that  disposition  of 
mind  prevail,  which  rve  should  be  apt  to  suppose  a 
necessary  result  of  their  peculiar  studies.  We  do 
not  discover  that  combination  of  genius  with  sound 
sense,  whicli  distinguished  Cuvier,  and  the  great 
men  of  seience.  It  is,  above  all,  surprising  ■\^fith  what 
perverse  ingenuiw  men  seek  to  obscure  the  concep- 
tion of  a Divine  Author,  an  intelligent,  designing, 
and  Irenevolent  Being — rather  clinging  to  the  great- 
est absurdities,  or  interposing  the  cold  and  inanunate 
influence  of  the  mere  elements,  in  a manner  to  extin- 
guish all  feeling  of  dependance  in  oirr  minds,  and  all 
emotions  of  gratitude. 

Some  will  maintain  that  all  the  varieties  which 
we  see,  are  the  result  of  a change  of  circumstances 
influencing  the  original  animal ; or  that  new  organs 
have  been  produced  by  a desire  and  consequent  eftbrt 
cf  the  animal  to  stretch  and  mould  itself — that,  as 
the  leaves  of  a plant  expand  to  light,  or  Uun  to  the 


SURROUNDING  INFLUENCE. 


113 


sun,  or  as  the  roots  shoot  to  the  appropriate  soil,  so 
do  the  exterior  organs  of  animals  grow  and  adapt 
themselves.  We  shall  presently  find  that  an  opinion 
has  prevailed  that  the  organization  of  animals  deter- 
mines their  propensities  ; but  the  philosophers,  of 
whom  we  are  now  speaking,  imagine  the  contrary, — 
that  under  the  influence  of  new  circumstances, 
organs  have  accommodated  themselves,  and  assumed 
their  particular  forms. 

It  must  be  here  remarked  that  there  are  no  in- 
stances of  the  production  of  new  organs  by  the 
union  of  individuals  belonging  to  different  species. 
Nor  is  there  any  foundation  in  observation  for  the 
opinion  that  a new  species  may  be  formed  by  the 
union  of  individuals  of  different  families.  But  it  is 
contended,  that,  although  the  species  of  animals  have 
not  changed  in  the  last  5000  years,  we  do  not  know 
what  might  have  been  the  effect  of  the  revolution  be- 
fore that  time ; that  is,  previous  to  the  present  condition 
of  the  world.  But,  on  subjects  of  this  nature,  we  must 
argue  from  what  we  know,  and  from  what  we  see. 

We  do  perceive  surprising  changes  in  the  con- 
formation of  animals ; some  of  them  are  very  fami- 
liar to  us  ; but  all  show  a foreknowledge  and  a pro- 
spective plan,  an  alteration  gradually  taking  place  in 
preparation  for  the  condition,  never  consequent  upon 
it.  It  will  be  sufficient  for  our  purpose,  if  we  take 
the  highest  and  the  lowest  examples.  Man  has  two 
conditions  of  existence  in  the  body.  Hardly  two 
creatures  can  be  less  alike  than  an  infant  and  a man. 
The  whole  foetal  state  is  a preparation  for  birth.  My 
readers  would  not  thank  me,  were  I to  show  how 
necessaiy  all  the  proportions  and  forms  of  the  infant 
are  to  his  being  born  alive, — and  yet  nothing  is  so 
easy  to  demonstrate.  Every  one  may  see  that  from 
the  moment  of  birth  there  is  a new  impulse  given  to 
the  growth,  so  as  finally  to  adapt  the  proportions  of 
the  body  to  the  state  of  perfect  manhood.  Few, 
however,  are  aware  that  the  foetus  has  a lije  adapted 


114 


THESE  THEORIES  INCORRECT. 


to  its  condition,  and  that  if  the  confinement  of  the 
womb  were  protracted  beyond  the  appointed  time,  it 
must  die  ! — from  no  defect  of  nourishment,  but  sim- 
ply, because  the  time  is  come  for  a change  in  its 
whole  economy  ! 

Now,  during  all  the  long  period  of  gestation,  the 
organs  are  forming''  the  lungs  are  perfected  before 
the  admission  of  air — new  tubes  are  constructed 
before  the  flood-gates,  which  are  to  admit  the  blood, 
are  opened.  But  there  are  finer,  and  more  curious, 
provisions  than  these.  If  Ave  take  any  of  the  grand 
organs,  as  the  heart,  or  the  brain,  and  examine  it 
througli  all  its  gradations  of  change  in  the  embryo 
state,  Ave  shall  recognize  it  simple,  at  first,  and  gra- 
dually developing,  and  assuming  the  pecuharities 
Avhich  finally  distinguish  it.  So  that  it  is  afiirmed, 
and  not  Avithout  the  support  of  a most  curious  series 
of  obseiwat ions,  that  the  human  brain,  in  its  earlier 
stage,  resembles  that  of  a fish  : as  it  is  developed,  it 
resembles  more  the  cerebral  mass  of  the  reptile  ; in 
its  increase,  it  is  like  that  of  a bird,  and  sloAvly,  and 
only  after  birth,  does  it  assume  the  proper  form  and 
consistence  of  the  human  encephalon.  But  in  all 
these  changes  to  Avhich  man  is  subject,  Ave  noAvhere 
see  the  influence  of  the  elements,  or  any  other  cause 
than  that  it  has  been  so  predestined.  And  if,  passing 
over  the  thousand  instances  Avhich  might  be  gathered 
fiom  the  intermediate  parts  of  the  chain  of  animal 
existence,  Ave  take  the  loAvest  link,  and  look  to  the  me- 
tamorphosis of  insects,  the  conclusion  AA'ill  be  the  same. 

For  example,  if  Ave  examine  the  larva  of  a Avinged 
insect,  Ave  shall  see  the  proA'isions  for  its  motion  over 
the  ground,  in  that  condition,  all  admirably  supplied 
in  the  arrangement  of  its  muscles,  and  the  distribu- 
tion of  its  nervous  sj'stem.  But  if,  anticipating  its 
metamorphosis,  Ave  dissect  the  same  larva  hinnedi- 
ately  before  the  change,  Ave  shall  find  a neAV  appara- 
tus in  progress  toAvards  perfection  ; the  muscles  of  iis 
many  feet  are  seen  decaying ; the  nerves  to  each 


THESE  THEORIES  INCORRECT. 


115 


muscle  are  wasting ; a new  arrangement  of  muscles, 
with  new  points  of  attachment,  directed  to  the  wings 
instead  of  the  feet,  is  now  visible  ; and  a new  distri- 
bution of  nerves  is  distinctly  to  be  traced,  accommo- 
dated to  the  parts  which  are  now  to  be  put  in  motion. 
Here  is  no  budding  and  stretching  forth  under  the 
influence  of  the  surrounding  elements  ; but  a change 
operated  on  all  the  economy,  and  prospective,  that  is, 
in  reference  to  a condition  which  the  creatiue  has  not 
yet  attained. 

These  facts  countenance  the  conclusion  di’awn 
from  the  comparative  anatomy  of  the  hand  and  arm — 
that  with  each  new  instrument,  visible  externally, 
there  are  a thousand  internal  relations  established  : a 
mechanical  contrivance  in  the  bones  and  joints,  which 
alters  every  part  of  the  skeleton  : an  arrangement  of 
muscles,  in  just  correspondence  ; a texture  of  nervous 
filaments,  which  is  laid  intermediate  between  the  in- 
strument and  the  very  centre  of  life  and  motion  ; and, 
finally,  as  we  shall  discover  from  what  follows,  new 
sources  of  activity  must  be  created  in  relation  to  the 
neiv  organ,  otherwise  the  part  will  hang  a useless 
appendage. 

It  must  now  be  apparent  that  nothing  less  than  the 
Power,  which  originally  created,  is  equal  to  the  eft'ect- 
ing  of  those  changes  on  animals,  which  are  to  adapt 
them  to  their  conditions  : that  their  organization  is 
predetermined,  and  not  consequent  on  the  condition  of 
the  earth  or  the  surrounding  elements.  Neither  can 
a property  in  the  animal  itself  account  for  the  changes 
Avhich  take  place  in  the  individual,  any  more  than 
for  the  varieties  which  take  place  in  the  species. 
Every  thing  declares  the  species  to  have  its  origin  in 
a distinct  creation,  not  in  a gradual  variation  from 
some  original  type  ; and  any  other  hypothesis  than 
tliat  of  a new  creation  of  animals  suited  to  the  succes- 
sive changes  in  the  inorganic  matter  of  the  globe — the 
condition  of  the  water,  atmosphere,  and  temperature — 
brings  with  it  only  an  accumulation  of  difficulties. 


CHAPTER  VII. 


OF  SENSIBILITY  AND  TOUCH. 

We  find  every  organ  of  sense,  with  the  exception 
of  that  of  touch,  more  perfect  in  brutes  than  in  man. 
In  the  eagle  and  the  hawk,  in  the  gazelle  and  in  the 
feline  tribe,  the  perfection  of  the  eye  is  admirable  ; — 
in  the  dog,  wolf,  hyaena,  as  well  as  in  birds  of  prey, 
the  sense  of  smelling  is  inconceivably  acute ; and  if 
we  should  have  some  hesitation  in  assigning  a more 
exquisite  sense  of  taste  to  brutes,  we  cannet  doubt 
the  superioi'ity  of  that  of  hearing  in  the  inferior  ani- 
mals. But  in  the  sense  of  touch,  seated  in  the  hand, 
man  claims  the  superiority ; and  it  is  of  consequence 
to  our  conclusion  that  we  should  observe  why  it  is  so. 

It  has  been  said  that,  accompanying  the  exercise  of 
touch,  there  is  a desire  of  obtaining  knowledge ; in 
other  words,  a detennination  of  the  will  towards  the 
organ  of  the  sense.  Bichat  says,  it  is  active  whilst 
the  other  senses  are  passive.  This  opinion  implies 
that  there  is  something  to  be  understood — something 
deeper  than  what  is  here  expressed.  We  shall  arrive 
at  the  truth  by  considering  that  in  the  use  of  the  hand 
there  is  a double  sense  exercised ; Ave  must  not  only 
feel  the  contact  of  the  object,  but  we  must  be  sen- 
sible to  the  muscular  eflTort  which  is  made  to  reach  it, 
or  to  grasp  it  in  the  fingers.  It  is  in  the  exercise  of 
this  latter  power  that  there  is  really  an  effort  made  ; 
there  is  no  more  direction  of  the  will  towards  the 
nerve  of  touch,  than  towards  any  other  sensible  nerve. 
But,  before  entering  on  the  consideration  of  the  sen- 
sibility and  action  Avhich  belong  to  the  fingers,  we 
must  attend  to  the  common  sensibility  of  the  surface. 


OF  SENSIBILITY  AND  TOUCH. 


m 


Besides  that  the  common  sensibility  belongs  to  the 
hand,  and  that  some  inquiry  into  it  is  necessary  to 
the  completion  of  our  subject,  I pursue  it  tlie  more 
Avillingly,  because  there  is  no  other  which  affords 
more  surprising  proofs  of  design  and  of  benevolence 
in  the  Author  of  our  being.  However  obvious  the 
proofs  may  be  which  are  drawn  from  the  mechanism 
of  the  body,  they  are  not  to  be  compared  Avith,  in 
this  respect,  to  those  which  are  derived  from  the  Iw- 
ing  endoAvments  of  the  frame. 

I ha\'e  used  the  term  common  sensibility  in  con- 
formity with  the  language  of  authors  and  with  cus- 
tomary parlance  ; but  the  expressions,  the  “ common 
nerves,”  and  the  “ conunon  sensibility,”  in  a philo- 
sophical inquiry,  are  inadmissible.  Indeed,  these 
terms  have  been  the  cause  of  much  of  the  obscurity 
which  has  hung  over  the  subject  of  the  nervous  s}'s- 
tem,  and  of  our  blindness  to  the  benevolent  adapta- 
tion of  the  endowments  of  that  system  to  the  condi- 
tion of  animal  existence.  Thus,  it  has  been  sup- 
posed that  some  nerves  are  more  coarsely  provided 
for  sensation,  and  that  others  are  of  a finer  quality, 
adapted  to  more  delicate  impressions.  It  is  assumed 
that  the  nerve  of  the  eye  is  finer  than  the  nerve  of 
the  finger — Avithout  considering  that  the  retina  is  in- 
sensible to  that  quality  of  matter  of  Avhich  Ave  readily 
acquire  the  knoAvledge  through  touch.  Nerves  are, 
indeed,  appropriated  to  peculiar  senses,  and  to  the 
bestoAving  of  distinct  functions,  but  delicacy  of  tex- 
ture has  nothing  to  do  Avuth  this.  The  nerr^e  of  touch 
in  the  skin  is  insensible  to  light  or  to  sound,  not  be- 
cause it  has  a coarser  or  more  common  textuie  : The 
beauty  and  perfection  of  the  system  is,  that  the  nenm 
is  made  susceptible  to  its  peculiar  impression  only. 
The  nerve  of  the  skin  is  alone  capable  of  giving  the 
sense  of  contact,  as  the  nerve  of  vision  is  confined  to 
its  oAvn  office.  If  this  appropriation  resulted  merelj^ 
from  a more  delicate  texture  : if  the  retina  Avere  sen- 
sible to  the  matter  of  light  only  from  possessing  a 


118 


SENSIBILITY  OF  THE  SURFACE 


finer  sensibility  than  the  nerve  of  touch,  it  would  be 
a source  of  torment ; whereas  it  is  most  beneficently 
provided  that  it  shall  not  be  sensible  to  pain,  nor  be 
capable  of  conveying  any  impressions  to  the  mind, 
but  those  Avhich  operate  according  to  its  proper  func- 
tion, producing  light  and  colour. 

The  pain  Avhich  Ave  experience  in  the  eye,  and  the 
irritation  from  dust,  are  owing  to  a distinct  neiwe  from 
that  of  vision,  and  are  consequent  on  the  suscepti- 
bility of  the  surface  to  a different  kind  of  impression  ; 
of  Avhich  more  presently.  We  should  keep  m mind 
the  interesting  fact,  that  Avhen  surgeons  perfonn  the 
operation  of  couching,  the  point  of  the  needle,  in 
passing  through  the  outer  coat  of  the  eA'e,  gives  a 
sensation  of  pricking,  Avhich  is  an  exercise  of  the 
nerve  of  touch ; but  Avhen  the  point  passes  through 
the  retina,  Avhich  is  the  expanded  nerve  of  vision  and 
form  tlie  internal  coat  of  the  ej’e,  the  sensation  that 
is  produced  is  as  of  a spark  of  fire.  The  nerve  of 
vision  is  as  insensible  to  touch  as  the  nerve  of  touch 
is  to  light.* 

The  extreme  sensibility  of  the  skin  to  the  slightest 
injury  conveys  to  everyone  the  notion — that  the  pain 
must  be  the  more  severe  the  deeper  the  wound.  This 
is  not  the  fact,  nor  would  it  accord  with  the  beneficent 
design  which  shines  out  every  where.  The  sensibility 
of  the  skin  serves  not  only  to  give  the  sense  of  touch, 
but  it  is  a guard  upon  the  deeper  parts  ; and  as  they 
cannot  be  reached  except  through  the  skin,  and  we 
must  suffer  pain,  therefore,  before  the}’  are  injured,  it 
would  be  superfluous  to  bestow  sensibility  upon  these 
deeper  parts.  If  the  internal  parts  which  act  in  the 
motions  of  the  body  had  possessed  a similar  degree 

* The  views  of  the  nen'ous  system,  \^’hich  are  shortly  given  in  tlie 
text,  guided  me  in  my  original  experiments  made  twenty-two  j'ears 
ago.  They  have  been  attributed  to  foreign  physiologists.  The  ig- 
norance of  what  has  been  done  in  England,  may  be,  for  strangers,  an 
excuse  for  maintaining  these  opinions  as  their  own  ; but  the  authors 
at  home,  who  should  have  known  what  lias  been  taught  in  tliis  coun- 
try, are  ine.xcusable  when  they  countenance  these  assumptions. 


COMPARED  WITH  THE  DEEPER  PARTS.  119 

and  kind  of  sensibility  with  the  skin,  so  far  from  serv- 
ing any  useful  purpose,  this  sensibility  would  have 
been  a source  of  inconvenience  and  continual  pain  in 
the  common  exercise  of  the  frame. 

The  reason  why  surgeons  more  than  physicians 
have  advanced  the  study  of  physiology,  may  be,  that 
they  become  practically  acquainted  with  the  pheno- 
mena on  which  the  science  is  founded.  The  surgeon 
who  has  to  perform  an  operation  by  incision,  when  he 
has  cut  through  the  skin,  informs  his  patient  that  the 
greatest  pain  is  over.  If,  in  the  advanced  stage  of 
the  operation,  he  has  to  extend  the  incision  of  the  skin, 
it  is  very  properly  considered  as  a great  awkwardness ; 
and  this  not  only  because  it  proves  that  he  has  mis- 
calculated what  was  necessary  to  the  correct  perform- 
ance of  his  operation,  but  because  the  patient,  bear- 
ing courageously  the  deeper  incisions,  cannot  sustain 
the  renewed  cutting  of  the  skin,  without  giving  tokei 
of  severe  pain. 

The  fact  of  the  exquisite  sensibility  of  the  surface, 
in  comparison  with  the  deeper  parts,  being  thus  as- 
certained by  daily  experience,  we  cannot  mistake  the 
intention  ; that  the  skin  is  made  a safeguard  to  the 
delicate  textures  which  are  contained  within,  by 
forcing  us  to  avoid  injiuies  : and  it  does  afford  us  a 
more  effectual  defence  than  if  oiu:  bodies  were  covered 
with  the  hide  of  the  rhinoceros. 

The  fuller  the  consideration  which  we  give  to  this 
subject,  the  more  convincing  are  the  proofs  that  the 
painful  sensibility  of  the  skin  is  a benevolent  provi- 
sion, making  us  alive  to  those  injuries,  which,  but  for 
this  quality  of  the  nervous  system,  would  bruise  and 
destroy  the  internal  and  vital  parts.  In  pursuing'  the 
inquiry,  we  learn  with  much  interest  that  when  the 
bones,  joints,  and  all  the  membranes  and  ligaments 
which  cover  them,  are  exposed — they  may  be  cut, 
pricked,  or  even  burned,  without  the  patient  or  the 
animal,  suffering  the  slightest  pain.  These  facts 
must  appear  to  be  conclusive  ; for  who,  witnessing 


120 


SENSIBILITY  TO  PAIN. 


these  instances  of  insensibility,  would  not  conclude 
that  the  parts  were  devoid  of  sensation.  But  when 
we  take  the  true,  philosophical,  and  I may  say  the 
religious  view  of  the  subject,  and  consider  that  pain 
is  not  an  evil,  but  given  for  benevolent  purposes  and 
for  some  important  object,  we  should  be  unwilling  to 
terminate  the  investigation  here. 

In  the  first  place,  we  must  perceive  that  if  a sensi- 
bility similar  to  that  of  the  skin  had  been  given  to 
these  internal  parts,  it  must  have  remained  miexer- 
cised.  Had  they  been  made  sensible  to  pricking  and 
burning,  they  would  have  possessed  a quality  which 
would  never  have  been  useful,  since  no  such  injmies 
can  reach  them ; or  never  without  warning  being 
received  through  the  sensibility  of  the  skin. 

But,  further,  if  we  find  that  sensibility  to  pain  is  a 
benevolent  provision,  and  is  bestowed  for  the  purpose 
of  warning  us  to  avoid  such  violence  as  would  affect 
the  functions  or  uses  of  the  parts,  we  may  yet  in- 
quire whether  any  injury  can  reach  these  internal 
parts  without  the  sensibility  of  the  skin  being  excited. 
Now,  of  this  there  can  be  no  doubt,  for  the}’  are  sub- 
ject to  sprain,  and  rapture,  and  shocks,  without  the 
skin  being  implicated  in  the  accident.  If  we  have 
been  correct  in  our  inference,  there  should  be  a jiro- 
vision  to  guide  us  in  the  safe  exercise  of  the  limbs  ; 
and  notwithstanding  what  has  been  apparently  de- 
monstrated of  the  insensibility  of  these  internal  parts, 
they  must  possess  an  appropriate  sensibility,  or  it 
would  imply  an  imperfection. 

With  these  reflections,  we  recur  to  experinrent — 
and  we  find  that  the  parts,  which  are  insensible  to 
pricking,  cutting,  and  burning,  are  actually  sensible 
to  concussion,  to  stretching,  or  laceration. 

How  consistent,  then,  and  beautiful  is  the  distribu- 
tion of  this  quality  of  life  ! The  sensibility  to  pain 
varies  with  the  function  of  the  part.  The  skin  is 
endowed  with  sensibility  to  every  possible  injurious 
impression  which  may  be  made  upon  it.  But  had 


PAIN  THE  SAFEGUARD  OF  THE  BODY. 


121 


this  kind  and  degree  of  sensibility  been  made  univer- 
sal, we  should  have  been  racked  with  pain  in  the  com- 
mon motions  of  the  body  : the  mere  weight  of  one  part 
on  another,  or  the  motion  of  the  joint,  would  have  been 
attended  with  that  degree  of  suffering  which  we  expe- 
rience in  using  or  walking  with  an  inflamed  limb. 

But  on  the  other  hand,  had  the  deeper  parts  pos- 
sessed no  sensibility,  we  should  have  had  no  guide 
in  our  exertions.  They  have  a sensibility  limited  to 
the  kind  of  injury  which  it  is  possible  may  reach 
them,  and  which  teaches  us  what  we  can  do  with 
impunity.  If  we  leap  from  too  great  a height,  or 
carry  too  great  a burthen,  or  attempt  to  interrupt  a 
body  whose  impetus  is  too  great  for  us,  we  are  warned 
of  the  danger  as  effectually  by  this  internal  sensibi- 
lity, as  we  are  of  the  approach  of  a sharp  point  or  a 
hot  iron  to  the  skin. 

Returning  to  the  consideration  of  the  sensibility 
of  the  skin,  in  order  more  fully  to  comprehend  the 
benevolent  effect  of  it,  or  in  other  words,  its  necessity 
to  our  very  existence,  I may  be  excused  for  stating 
the  argument  to  the  reader  as  I have  delivered  it  in 
my  lectures  to  the  College  of  Surgeons. 

“ Without  meaning  to  impute  to  you  inattention  or 
“ restlessness,  I may  request  you  to  observe  how  every 
“ one  occasionally  changes  his  position  and  shifts  tlie 
“ pressure  of  the  weight  of  his  body  ; were  you  con- 
“ strained  to  retain  one  position  during  the  whole 
“ hour,  you  would  rise  stiff  and  lame.  The  sensi- 
“ bility  of  the  skin  is  here  guiding  you  to  that,  which 
“ if  neglected,  would  be  followed  even  by  the  death 
“ of  the  part.  When  a patient  has  been  received 
“ into  the  hospital  with  paralysis  of  the  lower  part  of 
“ the  body,  we  must  give  especial  directions  to  the 
“ nurse  and  attendants  that  the  position  of  his  limbs 
“ should  be  changed  at  short  intervals,  that  pillows 
“ should  be  placed  under  his  loins  and  haras,  and  that 
“ they  should  be  often  shifted.  If  this  be  neglected, 
“ you  know  the  consequence  to  be  inflammation  of 

11 


122 


SENSIBILITY  TO  HEAT. 


“ the  parts  that  press  upon  the  bed  ; from  which  come 
“local  irritation,  then  fever  and  mortification  and 
“death. 

“ Thus  you  perceive  that  the  natural  sensibility  of 
“ the  skin,  without  disturbing  your  train  of  thought, 
“ induces  you  to  shift  the  body  so  as  to  permit  the  free 
“ circulation  of  the  blood  in  the  minute  vessels ; and 
“ that  when  this  sensibility  is  wanting,  the  utmost 
“ attention  of  friends  and  the  watchfulness  of  the 
“ nurse  are  but  a poor  substitute  for  this  protection 
“ which  nature  is  continually  aflfording.  If  you  suf- 
“ fer  thus  lying  on  a soft  bed,  when  deprived  of  the 
“ sensibility  of  the  skin,  how  could  you  encounter 
“ without  it  the  rubs  and  impulses  incident  to  an  ac- 
“ tive  life  ? You  must  now  acknowledge  that  the 
“ sensibility  of  the  skin  is  as  much  a protection  to  the 
“ frame  generally,  as  the  sensibility  of  the  ej'elids  is 
“ to  the  eyes,  and  gives  you  a motive  for  gi’atitude 
“ which  probably  you  never  thought  of.” 

The  sensibility  of  the  hand  to  heat,  is  a different 
endowment  from  that  of  touch.  This  sensibility  to 
the  varieties  of  temperature  is  seated  in  the  skin,  and 
is,  consequently,  limited  to  the  exterior  siuface  of  the 
body.  The  internal  parts  of  the  body  being  of  a imi- 
form  temperature,  it  would  have  been,  in  them,  a 
quality  altogether  superfluous.  But  as  we  are  sur- 
rounded by  a temperatm’e  continually  varjdng,  and 
are  subject  to  destruction  by  its  extremes,  and  as  we 
must  suit  our  exertions  or  our  contrivances  so  as  to 
sustain  life  against  these  vicissitudes,  our  possession 
of  this  peculiar  sensibility  on  the  surface  affords 
another  proof  of  there  havmg  been  a foreknow- 
ledge of  our  condition.  We  might,  indeed,  take 
our  former  example  in  evidence  of  what  must  befal 
through  the  want  of  this  sensibility — the  paralytic  is 
brought  to  us  severely  burned,  or  with  his  extremities 
mortified  through  cold.  A man  having  lost  the  sense 
of  heat  in  his  right  hand,  but  retaining  the  muscular 
power,  lifted  the  cover  of  a pan  which  had  fallen  into 


SENSIBILITY  OF  HEAT. 


123 


the  fire  and  deliberately  replaced  it,  not  being  con- 
scious that  it  was  burning  hot ; the  effect,  however, 
was  the  death  and  destruction  of  the  skin  of  the 
palm  and  fingers.  In  this  man  there  was  a continual 
sensation  of  coldness  in  the  affected  arm,  which 
actual  cold  applied  to  the  extremity  did  not  aggra- 
vate nor  heat  in  any  degree  assuage.*  Sensibility 
to  heat  is  a safeguard  in  as  much  as  it  is  capable  of 
becoming  a painful  sensation,  whilst  it  is  a never- 
failing  excitement  to  activity  and  a continual  source 
of  enjoyment. 

And  here  we  may  remark  an  adaptation  of  the 
living  property  very  different  from  the  physical  in- 
fluence. Heat  is  uniform  in  its  effect  on  matter ; but 
the  sensation  varies  as  it  is  given  or  abstracted  from 
the  living  body.  Cold  and  heat  are  distinct  sensa- 
tions ; and  this  is  so  far  important  that  without  such 
contrast  we  should  not  continue  to  enjoy  the  sense. 
For  in  the  nervous  system  it  holds  universally  that 
variety  or  contrast  is  necessary  to  sensation,  the  finest 
organ  of  sense  losing  its  property  by  the  continuance 
of  the  same  impression.  It  is  by  a comparison  of 
cold  and  heat  that  we  enjoy  either  condition. 

To  contrast  still  more  strongly  the  sensibility  of 
the  surface  with  the  property  of  internal  parts,  to 
shew  how  very  different  sensibility  is,  in  reality,  from 
what  is  suggested  by  first  experience,  and  how  admi- 
rably it  is  varied  and  accommodated  to  the  functions, 
we  shall  add  one  other  fact.  The  brain  is  insensible 
— that  part  of  the  brain,  which  if  disturbed  or  dis- 
eased, takes  away  consciousness,  is  as  insensible  as 
the  leather  of  our  shoe  ! That  the  brain  may  be 
touched,  or  a portion  of  it  cut  off,  without  interrupting 
the  patient  in  the  sentence  that  he  is  uttering,  is  a 
surprising  circumstance  ! From  this  fact  Physiolo- 
gists formerly  inferred  that  the  surgeon  had  not 

* There  are  certain  morbid  conditions  of  sensation  when  cold 
bodies  feel  intensely  hot. — Dr.  Abercrombie' s Inquiry  into  the  Intel- 
lectual powers. 


124 


SENSIBILITY  OF  THE  EYE. 


reached  the  more  important  organ  of  the  brain.  But 
that  opinion  arose  from  the  notion  prevailing  that  a 
nerve  must  necessarily  be  sensible.  Whereas,  '^hen 
we  consider  that  the  different  parts  of  the  neiwous  sys- 
tem have  totally  distinct  endowments,  and  that  therfe 
are  nerves,  as  1 have  elsewhere  shewn,  insensible  to 
touch  and  incapable  of  giving  pain,  though  exquisite- 
ly alive  to  their  proper  office,  we  have  no  just  reason 
to  conclude  that  the  brain  should  be  sensible,  or 
exhibit  the  property  of  a nerve  of  the  skin.  Reason 
on  it  as  we  may,  the  fact  is  so  ; — the  bram,  through 
which  every  impression  must  be  conveyed  before  it  is 
perceived,  is  itself  insensible.  This  informs  us  that 
sensibility  is  not  a necessary  attendant  on  the  delicate 
texture  of  a living  part,  but  that  it  must  have  an 
appropriate  organ,  and  that  it  is  an  especial  provi- 
sion.* 

To  satisfy  my  reader  on  this  interesting  subject,  1 
shall  take  the  contrast  of  two  organs,  one  external 
and  exposed,  and  the  other  internal  and  carefully 
excluded  from  injury. 

The  eye,  consisting  of  its  proper  ner\'e  of  vision 
and  its  transparent  humours  and  coats,  is  an  organ 
of  exquisite  delicacy — not  only  is  it  exposed  to  all 
the  injuries  to  which  the  general  surface  of  the  bod\' 
is  liable,  but  to  be  inflamed  and  rendered  opaque  by 
particles  getting  into  it  which  are  so  light  that  they 
float  in  the  atmosphere,  and  to  the  contact  of  which 
the  common  skin  is  quite  insensible.  The  mechani- 
cal, and  more  obvious  contrivance  for  the  protection 
of  this  organ,  is  a ready  motion  of  the  e5'elids  and  the 
shedding  of  tears ; which  coming,  as  it  were,  from  a 
little  fountain,  play  over  the  surface  of  the  eye,  and 
Avash  awaj’ whatever  is  ofl'ensive.  But  to  the  action 
of  this  little  hydraulic  and  mechanical  apparatus  there 
is  required  an  exquisite  sensibility  to  direct  it — not  that 
kind  of  sensibility  which  enables  the  eye  to  receive 


* See  the  Sensibility  of  the  Retina,  Appendix. 


SENSIBILITY  OF  THE  EYE. 


125 


the  impressions  of  ligiit — but  a property  more  resem- 
bling the  tenderness  of  the  skin,  yet  happily  adapted, 
by  its  fineness,  to  the  condition  of  the  organ. 

A nerve,  possessed  of  a quality  totally  different 
from  that  of  the  optic  nerve,  extends  over  all  the  ex- 
terior surfaces  of  the  eye,  and  gives  to  those  surfaces 
their  delicate  sensibility.  Now  it  sometimes  hap- 
pens that  this  nerve  is  injured  and  its  function  lost ; 
the  consequences  of  which  are  very  curious, — smoke 
and  offensive  particles,  which  are  afloat  in  the  atmos- 
phere, rest  upon  the  eye  : flies  and  dust  lodge  under 
the  eyelids,  without  producing  sensation,  and  with- 
out exciting  either  the  hydraulic  or  the  mechanical 
apparatus  to  act  for  the  purpose  of  expelling  them. 
But  although  they  do  not  give  pain,  they  neverthe- 
less stimulate  the  surfaces  so  as  to  produce  inflamma- 
tion, and  that  causes  opacity  in  the  fine  transparent 
membranes  of  the  eye  ; and  the  organ  is  lost,  al- 
though the  proper  nerve  of  vision  remains  entire. 
I have  seen  many  instances  of  the  eye  being  thus 
destroyed  for  want  of  sensibility  to  touch,*  and  it 
has  been  curious  to  remark  that  when  the  hand  was 
waved  or  a feather  brought  near  the  eye,  the  person 
winked ; yet  he  did  not  shut  his  eye  on  rubbing  the 
finger  across  the  eyeball,  or  when  blood  was  removed 
by  the  lancet  from  the  inflamed  vessels.  In  those 
cases,  when  vision  gave  notice  of  danger  to  the  or- 
gan, the  patient  winked  to  avoid  it,  but  when  the 
point  touched  the  eye  or  eyelids,  the  sense  of  touch 
gave  no  alarm,  and  was  followed  by  no  action  for  the 
protection  of  the  organ. 

I shall  present  another  instance  of  the  peculiar  na- 
ture of  the  sensibility  which  protects  the  eye.  The 
Oculist  has  observed  that  by  the  touch  of  a thing  as 
light  as  a feather,  the  muscles  of  the  eye  will  be 
thrown  into  uncontrollable  actions  and  spasms  ; but  if 
the  point  of  the  finger  be  pressed  somewhat  rudely 

* They  are  stated  at  length  in  my  papers  in  the  Philosophical 
Transactions,  and  in  the  Appendix  of  my  work  on  the  Nervous  System. 

11* 


J26  SENSIBILITY  OF  THE  HEART. 

between  the  eyelids,  and  directly  on  the  eye  itself,  he 
can  by  such  means  hold  the  eye  steady  for  his  intend- 
ed operation,  producing  hardly  any  sensation,  certain- 
ly no  pain  ! 

This  is  one  of  the  little  secrets  of  the  art ; the  Ocu- 
list turns  out  the  eyelids,  and  fingers  the  eye,  in  a 
manner  which  appears,  at  once,  rude  and  masterly: 
and  still  the  wonder  grows  that  he  can  do  such 
things  with  so  much  dexterity  as  to  inflict  no  pain, 
when  by  daily  experience  we  know  that  even  a grain 
of  sand  in  the  eye  will  torture  us.  The  explanation 
is  this  : the  eye  and  eyelids  are  possessed  of  a sensi- 
bility which  is  so  adjusted  as  to  excite  the  action  ot 
its  protecting  parts  against  such  small  particles  as 
might  lodge  and  inflame  its  fine  membranes.  But 
the  apparatus  is  not  capable  of  protecting  the  surface 
of  the  eye  against  the  intrusion  of  a stick  or  a stone  ; 
from  such  injuries  it  could  not  be  defended  by  a deli- 
cate sensibility  and  involuntary  action,  but  only  by 
the  effort  of  the  will. 

In  these  details  we  have  new  proofs  of  the  minute 
relation  which  is  established  between  the  species  of 
sensibility  in  an  organ  and  the  end  to  be  attained 
through  it.  It  will  not  be  denied  that  but  for  the 
pain  to  which  the  eye  is  exposed,  we  should  quickly 
lose  the  enjoyment  of  the  sense  of  \ision  altogether. 
But  we  were  about  to  institute  a comparison  of  the 
eye  with  the  heart. 

The  observation  of  the  admirable  Harvey,  the  dis- 
coverer of  the  circulation  of  the  blood,  is  to  this 
effect.  A noble  youth  of  the  family  of  Montgomery, 
from  a fall  and  consequent  abscess  on  the  side  of  the 
chest,  had  the  interior  marvellouslj'  exposed,  so  that 
after  his  cure,  on  his  return  from  his  travels,  the  heart 
and  lungs  were  still  visible  and  could  be  handled  ; 
which  when  it  was  communicated  to  Charles  I.,  he 
expressed  a desire  that  Harvey  should  be  permitted 
to  see  the  youth  and  examine  his  heart.  “ When,” 
says  Harvey,  “ I had  paid  my  respects  to  this  young 


SENSIBILITIES  OP  EXTERNAL  PARTS,  &C.  127 

“ nobleman,  and  conveyed  to  him  the  king’s  request, 
“ he  made  no  concealment,  but  exposed  the  left  side 
“ of  his  breast,  when  I saw  a cavity  into  which  I 
“ could  introduce  my  fingers  and  thumb  ; astonished 
“ with  the  novelty,  again  and  again  I explored  the 
“ wound,  and  first  marvelling  at  the  extraordinary 
“ nature  of  the  cure,  I set  about  the  examination  of 
“ the  heart.  Taking  it  in  one  hand,  and  placing  the 
“ finger  of  the  other  on  the  pulse  of  the  wrist,  I 
“ satisfied  myself  that  it  was  indeed  the  heart  which 
“ I grasped.  I then  brought  him  to  the  king  that 
“ he  might  behold  and  touch  so  extraordinary  a thing, 
“ and  that  he  might  peiceive,  as  I did,  that  unless 
“ when  we  touched  the  outer  skin,  or  when  he  saw 
“ our  fingers  in  the  cavity,  this  young  nobleman 
“ knew  not  that  we  touched  his  heart !”  Other  ob- 
servations confirm  this  great  authority,  and  the  heart 
is  declared  insensible.  And  yet  the  opinions  of  man- 
kind must  not  be  lightly  condemned.  Not  only  does 
every  emotion  of  the  mind  affect  the  heart,  but  every 
change  in  the  condition  of  the  body  is  attended  with 
a corresponding  change  in  the  heart : motion  during 
health — the  influence  of  disease — every  passing 
thought  will  influence  it.  Here  is  the  distinction 
manifested.  The  sensibility  of  the  surface  of  the 
eye  is  for  a purpose,  and  so  is  the  sensibility  of  the 
heart.  Whilst  that  of  the  eye  guards  it  against  in- 
jury from  without,  the  heart,  insensible  to  touch,  is 
yet  alive  to  every  variation  in  the  circulation,  subject 
to  change  from  every  alteration  of  posture  or  of 
exertion,  and  is  in  sympathy  of  the  strictest  kind 
with  the  constitutional  powers. 

When  we  consider  these  facts,  we  can  no  longer 
doubt  that  the  sensibilities  of  the  living  frame  are  ap- 
propriate endowments  ; not  qualities  necessarily  aris- 
ing from  life  ; still  less  the  consequences  of  delicacy 
of  texture.  Nor  can  we,  I should  hope,  longer  doubt 
that  they  are  suited  to  the  condition,  and  especially 
to  the  degree  of  exposure  of  each  part,  and  for  its  pro- 


128  PLEASURABLE  SENSATIONS  COULD  NOT 

tection.  We  perceive  that  the  sensibilities  vary  in 
an  extraordinary  manner  as  they  are  given  to  exter- 
nal or  to  internal  parts,  asthej’^  belong  to  one  appara- 
tus of  action  or  to  another,  and  they  are  ever  adapted 
to  excite  some  salutary  or  necessary  action.  We 
perceive  no  instance  of  pain  being  bestowed  as  a 
source  of  suffering  or  punishment  purely,  or  without 
finding  it  overbalanced  by  great  and  essential  advan- 
tages— without,  in  short,  being  forced  to  admit  that 
no  happier  contrivance  could  be  found  for  the  pro- 
tection of  the  part.  It  is  provided  that  the  more  an 
organ  is  exposed,  and  in  proportion  to  its  delicacy  of 
organization — the  more  exquisitely  contrived  is  the 
apparatus  for  its  protection,  and  tlie  more  peremptory 
the  call  for  the  activity  of  that  mechanism.  The 
motive  to  action  admits  of  no  thought  and  no  hesita- 
tion, and  the  action  is  more  instantaneous  than  the 
quickest  suggestion  or  impulse  of  the  will. 

We  are  speaking  of  the  natural  functions  of  thebod}'. 
It  requires  a deeper  consideration,  and  is  indeed  fo- 
reign to  my'  subject  to  speak  of  the  pains  which  result 
from  disease,  or  to  reconcile  those  who  suffer  in  an 
extraordinary  degree  to  the  dispensations  of  Provi- 
dence. But  as  a witness  I may  speak.  It  is  my  dai- 
ly duty  to  visit  certain  wards  of  the  hospital,  where 
there  is  no  patient  admitted  but  with  that  complaint 
which  most  fills  the  imagination  \\'ith  the  idea  of  in- 
sufferable pain  and  certain  death.  Yet  these  wards 
are  not  the  least  remarkable  for  the  composure  and 
cheerfulness  of  their  inmates.  The  individual  who 
suffers  has  a my'sterious  counterbalance  to  that  con- 
dition, which  to  us  who  look  upon  her,  appears  to  be 
attended  with  no  alleviating  circumstance. 

It  affords  an  instance  of  the  boldness  with  which 
philosophers  have  questioned  the  ways  of  Providence, 
that  they  have  asked — why^  were  not  all  cur  actions 
performed  at  the  suggestion  of  pleasure  1 why  should 
w'e  be  subject  to  pain  at  all?  In  answer  to  this  I 
should  say',  in  the  first  place,  that  consistently  with 


HAVE  BEEN  THE  MOTIVES  TO  ACTION.  129 

our  condition,  our  sensations  and  pleasures,  there 
must  be  variety  in  the  impressions  ; such  contrast  and 
variety  are  common  to  every  variety^  of  sense  ; and 
the  continuance  of  an  impression  on  any  one  organ, 
occasions  it  to  fade.  If  the  eye  continue  to  look 
steadfastly  upon  one  object,  the  image  is  soon  lost — 
if  we  continue  to  look  on  one  colour,  we  become  in- 
sensible to  that  colour,  and  opposite  colours  to  each 
other  are  necessary  for  a perfect  impression.  So  have 
we  seen  that  in  the  insensibilities  of  the  skin  varia- 
tions are  necessary  to  continued  sensation. 

It  is  difficult  to  say  what  these  philosophers  would 
define  as  pleasure : but  whatever  exercise  of  the 
senses  it  should  be,  unless  we  are  to  suppose  an 
entire  change  of  our  nature,  its  opposite  is  also 
implied.  Nay,  further,  in  this  fanciful  condition  of 
existence,  did  anything  of  our  present  nature  prevail, 
emotions  purely  of  pleasure  would  lead  to  indolence, 
relaxation,  and  indifference.  To  what  end  should 
there  be  an  apparatus  to  protect  tire  eye,  since  plea- 
sure could  never  move  us  to  its  exercise?  Could  the 
windpipe  and  the  interior  of  the  lungs  be  protected 
by  a pleasurable  sensation  attended  with  the  slow 
determination  of  the  will — instead  of  the  rapid  and 
powerful  influence  which  the  exquisite  sensibility  of 
the  throat  has  upon  the  act  of  respiration,  or  those 
forcible  yet  regulated  exertions,  which  nothing  but 
the  instinctive  apprehension  of  death  could  excite  ? 

To  suppose  that  we  could  be  moved  by  the  solici- 
tations of  pleasure  and  have  no  experience  of  pain, 
would  be  to  place  us  where  injuries  would  meet  us 
at  every  step  and  in  every  motion,  and  whether  felt 
or  not,  would  be  destructive  to  life.  To  suppose 
that  we  are  to  move  and  act  without  experience  of 
resistance  and  of  pain,  is  to  suppose  not  onl)^  that 
man’s  nature  is  changed,  but  the  whole  of  exterior 
nature  also — there  must  be  nothing  to  bruise  the 
body  or  hurt  the  eye,  nothing  noxious  to  be  drawn  in 
with  the  breath  : in  short,  it  is  to  imagine  altogether 


130 


PAIN  NECESSARY  TO  EXISTENCE. 


another  state  of  existence,  and  the  philosopher  would 
be  mortified  were  we  to  put  this  interpretation  on  his 
meaning.  Pain  is  the  necessary  contrast  to  pleasure : 
it  ushers  us  into  existence  or  consciousness  : it  alone 
is  capable  of  exciting  the  organs  into  activity  ; it  is 
the  companion  and  the  guardian  of  human  life. 


CHAPTER  VIII. 


OF  THE  SENSES  GENERALLY,  INTRODUCTORY  TO 
THE  SENSE  OF  TOUCH. 

Although  we  are  most  familiar  with  the  sensibili- 
ty of  the  skin,  and  believe  that  we  perfectly  under- 
stand the  nature  of  the  impressions  upon  it  and  the 
mode  of  their  conveyance  to  the  sensorium,  yet  there 
is  a difficulty  in  comprehending-  the  operations  of  all 
the  organs  of  the  senses — a difficidty  not  removed  by 
the  apparent  simplicity  of  that  of  touch. 

There  was  a time  when  the  enquirer  was  satisfied 
on  finding  that  in  the  ear  there  was  a little  drum  and 
a bone  to  play  upon  it,  with  an  accompanying  nerve. 
This  was  deemed  a sufficient  explanation  of  the 
organ  of  hearing.  It  was  thought  equally  satisfacto- 
ry if  in  experimenting  upon  the  eye,  the  image  was 
seen  painted  at  the  bottom  of  it  on  the  surface  of  the 
nerve.  But  although  the  impression  be  thus  traced 
to  the  extremity  of  the  nerve,  still  we  comprehend 
nothing  of  the  nature  of  that  impression,  or  of  the 
manner  in  which  it  is  transmitted  to  the  sensorium. 
To  the  most  minute  examination,  the  nerves,  in 
all  their  course,  and  where  they  are  expanded  into 
the  external  organs  of  sense,  seem  the  same  in  sub- 
stance and  in  structure.  The  disturbance  of  the 
extremity  of  the  nerve,  the  vibrations  upon  it,  or  the 
images  painted  upon  its  surface,  cannot  be  transmit- 
ted to  the  brain  according  to  any  physical  laws  that 
we  are  acquainted  with.  The  impression  on  the 
nerve  can  have  no  resemblance  to  the  ideas  suggest- 
ed in  the  mind.  All  that  we  can  say  is,  that  the 
agitations  of  the  nerves  of  the  outward  senses  are  the 


132 


ORIGIN  OF  IDEAS. 


signals,  which  the  Author  of  nature  has  made  the 
means  of  correspondence  with  the  reeJities.  There 
is  no  more  resemblance  between  the  impressions  on 
the  senses  and  the  ideas  excited  by  them,  than  there 
is  between  the  sound  and  the  conception  raised  in 
the  mind  of  that  man  who,  looking  out  on  a dark  and 
stormy  sea,  hears  the  report  of  cannon,  which  con- 
veys to  him  the  idea  of  despair  and  shipwreck — or 
between  the  impression  of  light  on  the  eye,  and  the 
idea  of  him  who,  having  been  long  in  terror  of  nation- 
al convulsion,  sees  afar  off  a column  of  flame,  wliich 
is  the  signal  of  actual  revolt. 

By  such  illustrations,  however,  we  rather  show  the 
mind’s  independence  of  the  organ  of  sense,  and  how 
a tumidt  of  ideas  will  be  excited  by  an  impression  on 
the  retina,  which,  notwithstanding,  may  be  no  more 
intense  than  that  produced  by  a burning  taper. 
They  are  instances  of  excited  imagination.  But 
even  the  determined  relations  which  are  established 
in  a common  act  of  perception  between  the  sensation 
and  the  idea  in  the  mind,  have  no  more  actual  resem- 
blance. How  the  consent,  which  is  so  precise  and 
constant,  is  established,  can  neither  be  explained  by 
anatomy  nor  by  physiology,  nor  by  any  mode  of  phy- 
sical inquiry  whatever. 

From  this  law  of  our  nature,  that  certain  ideas 
originate  in  the  mind  in  consequence  of  the  operation 
of  coiTesponding  nerves,  it  follows — that  one  organ 
of  sense  can  never  become  the  substitute  for  another, 
so  as  to  excite  in  the  mind  the  same  idea. 

When  an  individual  is  deprived  of  the  organs  of 
sight,  no  power  of  attention,  or  continued  effort  of  the 
will,  or  exercise  of  the  other  senses,  can  make  him 
enjoy  the  class  of  sensations  which  is  lost.  The 
sense  of  touch  may  be  increased  in  an  exquisite  de- 
gree ; but  were  it  true,  as  has  been  asserted,  that  in- 
dividuals can  discover  colours  by  the  touch,  it  could 
only  be  by  feeling  a change  upon  the  surface  of  the 
stuff  and  not  by  any  perception  of  the  colour.  It  has 


ORIGIN  OF  IDEAS. 


133 


been  my  painful  duty  to  attend  on  persons  iviio  have 
pretended  blindness  and  that  they  could  see  with  their 
lingers.  But  I have  ever  found  that  by  a deviation 
from  truth  in  the  first  instance,  they  have  been  en- 
tangled in  a tissue  of  deceit ; and  have  at  last  been 
forced  into  admissions  which  demonstrated  their  fol- 
ly and  weak  inventions.  I have  had  pity  for  such 
patients  when  they  have  been  the  subjects  of  nervous 
disorders  which  have  produced  extraordinary  sensi- 
bility in’  their  organs — such  as  a power  of  hearing 
much  beyond  our  common  experience  ; for  it  has  at- 
tracted high  interest  and  admiration,  and  has  gradu- 
ally led  them  to  pretend  to  powers  greater  than  they 
actually  possessed.  In  such  cases  it  is  difiicult  to 
distinguish  the  symptoms  of  disease,  from  the  pre- 
tended gifts  which  are  boasted  of. 

Experiment  proves,  what  is  suggested  by  Anatomy, 
that  not  only  the  organs  are  appropriated  to  particular 
classes  of  sensations,  but  that  the  nerves,  intermediate 
between  the  .brain  and  the  outward  organs,  are  re- 
spectively capable  of  receiving  no  other  sensations 
but  such  as  are  adapted  to  their  particular  organs. 

Every  impression  on  the  nerve  of  the  e}"e,  oi  of  the 
ear,  or  on  the  nerve  of  smelling,  or  of  taste,  excites 
only  ideas  of  vision,  of  hearing,  of  smelling,  or  of  tast- 
ing ; not  solely  because  the  extremities  of  these  nerves, 
individually,  are  suited  to  external  impressions,  but 
because  tlie  nerves  are,  through  their  whole  course 
and  wdierever  they  are  irritated,  capable  of  exciting 
in  the  mind  the  idea  to  which  they  are  appropriate, 
and  no  other.  A blow,  an  impulse  quite  unlike  that 
for  which  the  organs  of  the  senses  are  provided,  will 
excite  them  all  in  tiieir  several  ways  ; the  eyes  will 
flash  fire,  while  there  is  noise  in  the  ears.  An  officer 
received  a musket-ball  which  went  through  the  bones 
of  his  face — in  describing  his  sensations,  he  said  that 
he  felt  as  if  there  had  been  a flash  of  lightning,  accom- 
panied with  a sound  like  the  shutting  of  the  door  of 
St.  Paul’s. 


12 


134 


MORBID  SENSATIONS. 


On  this  circumstance,  of  every  neiTe  being  appro- 
priated to  its  function,  depend  the  false  sensations 
which  accompany  the  morbid  irritation  of  them  from 
internal  causes,  when  there  is  in  reality  nothing  pre- 
sented externally  — such  as  flashes  of  light,  ringing 
of  the  ears,  and  bitter  taste  or  offensive  smells. 
These  sensations  are  caused,  through  the  excitement 
of  the  respective  nerves  of  sense,  by  derangement  of 
some  internal  organ,  and  most  frequently  of  the  sto- 
mach. 

But  my  chief  object  is  to  show  that  the  most  per- 
fect proof  of  power  and  of  design,  is  to  be  found  in 
this,  that  the  perceptions  or  ideas  arising  in  the  mind, 
are  in  correspondence  with  the  qualities  of  external 
matter ; and  that,  although  the  manner  in  which 
the  object  presented  to  the  ouUvard  sense  and  the 
idea  of  it  are  connected,  must  ever  be  beyond  our 
comprehension,  the}*  are,  notwithstanding,  indissolu- 
bly united  ; and  when  the  object  is  so  presented  to 
us,  it  is  attended  with  the  con^’iction  of  its  real  exis- 
tence—a conviction  independent  of  reason  and  to  be 
regarded  as  a first  law  of  our  nature. 

The  doctrine  of  vibrations  acting  on  the  nerve  of 
vision,  has  had  powerful  advocates  in  our  day.  But 
it  is  quite  at  variance  with  anatomy,  and  assumes 
more  than  is  usually  granted  to  ht’potheses.  It 
requires  that  we  shall  imagine  the  existence  of  an 
ether  ; and  that  this  fluid  shall  have  laws  unlike 
anything  of  which  we  have  experience.  It  supposes 
a nervous  fluid  and  tubes  of  fibres  in  the  ner\'e,  to 
receive  and  convey  these  vibiations.  It  supposes 
eveiywhere  motion  as  the  sole  means  of  propagating 
sensation. 

These  opinions  have  been  formed  on  the  miscon- 
ception that  if  a certain  kind  or  degree  of  vibration 
be  communicated  to  any  nerve,  this  particular  motion 
must  be  propagated  to  the  sensorium,  and  a corres- 
ponding idea  excited  in  the  mind.  For  example,  it 
is  conceived  that  if  the  nerve  of  hearing  were  placed 


DOCTRINE  OF  UNDULATIONS. 


135 


in  the  bottom  of  the  eye,  it  would  be  impressed  with 
the  vibration  proper  to  light,  and  that  this  being  con- 
veyed to  the  brain,  the  sensation  of  light  or  colours 
would  result — All  which  is  contrary  to  fact. 

Noi  can  I be  satisfied  that  light  and  colours  shall 
result  from  vibrations  which  shall  vary  “ from  four 
“hundred  and  fifty  eight  millions  of  millions,  to 
“ seven  hundred  and  twenty  seven  millions  of  mil- 
“ lions  in  a second,”  when  I find  that  a fine  needle 
pricking  the  retina  will  produce  brilliant  light,  and 
that  the  pressure  of  the  finger  on  the  ball  of  the  eye 
will  give  rise  to  all  the  colours  of  tlie  rainbow  ! 

There  is  a condition  of  the  percipient  or  sentient 
principle,  of  the  brain  and  nerves,  as  well  as  of  the 
organ  of  sense,  conforming  to  the  impression  to  be 
made  ; a condition  which  corresponds  with  the  quali- 
ties of  matter.  The  several  organs  of  sense  may  be 
compared  to  so  many  instruments,  which  the  philoso- 
pher applies  to  distinguish  the  several  cpialities  of  the 
body  wliich  he  investigates.  The  diflerent  proper- 
ties of  that  body  are  not  communicable  through  any 
one  instrument ; and  so  in  the  use  of  the  senses, 
each  organ  is  provided  for  receiving  a particidar 
influence,  and  no  other. 

However  mortifying  it  may  be  to  acknowledge 
ignorance,  variation  of  motion  in  a body  cannot  be 
admitted  as  the  cause  of  sensation  universally  ; nor, 
as  I said,  can  we  comprehend  anything  of  the  man- 
ner in  which  the  nerves  are  affected  ; certainly  we 
know  nothing  of  the  manner  in  which  sensation  is 
propagated  or  the  mind  ultimately  influenced.  But 
there  is  a very  pleasing  view  of  the  subject,  notwith- 
standing ; which  is  to  observe  the  correspondence 
of  the  mind  (through  a series  of  organic  parts)  with 
the  external  world,  or  with  the  condition  and  quali- 
ties of  matter  : than  which  nothing  can  convey  a 
more  sublime  idea  of  Power,  and  of  the  system  or 
unity  of  organic  and  inorganic  creations. 

Returning  to  the  consideration  of  the  sensibility  of 


138 


OF  TOUCH. 


the  skin  and  the  sense  of  touch,  this  property  is  as 
distinct  an  endowment  as  that  which  belongs  to  the 
eye.  It  is  neither  inferior  nor  more  common.  It  is 
not  consequent  upon  the  mere  exposure  of  the 
delicate  surface  of  the  animal  body.  It  is  a distinct 
sense,  the  organ  of  which  is  seated  in  the  skin  ; and 
it  is  necessary  that  this  organ  of  sense  should  be 
extended  widely  over  the  surface  of  the  body,  "iet 
the  nerves  are  as  appropriate  and  distinct  as  if  they 
were  gathered  into  one  trunk,  such  as  we  find  them 
to  be  in  the  organs  of  vision  and  hearing. 

Although  the  portion  of  nervous  matter  on  which 
the  sensation  and  perception  of  touch  depend,  be 
necessarily  extended  in  its  sentient  extremities  over 
the  whole  exterior  surface  of  the  bodjq  it  is  very 
much  concentrated  towards  the  brain ; and  it  is 
there  appropriated,  in  the  same  manner  as  the  nerves 
of  vision  and  of  hearing,  to  its  peculiar  firnction  of 
raising  corresponding  perceptions  in  the  mind. 

Perhaps  this  will  be  better  understood  from  the 
fact — that  a certain  large  portion  of  the  skitr  may  be 
the  seat  of  excrrrciating  pain,  and  j’et  the  smface, 
which  to  the  patierrt’s  perception  is  the  seat  of  that 
pain,  will  be  altogether  insensible  to  cutting,  burning, 
or  arry  mode  of  destrirction  ! “ I have  no  feeling  in 

“ all  the  side  of  my  face,  and  it  is  dead  ; yet  surely 
“ it  cannot  be  dead,  since  there  is  a constant  pricking 
“pain  in  it.”  Such  were  the  words  of  a 3-oung 
woman  whose  disease  was  at  the  root  of  the  irerve  of 
serrsibility  near  the  brain.*  The  disease  destroyed 
the  frrnction  of  this  nerve  of  the  head,  as  to  its  pro- 
perty of  corrve3’ing  sensation  from  the  exterior  ; aird 
substituted  that  morbid  inrpressiori  on  the  trunk 
whicli  was  referred  to  the  tactile  extremities. 

If  we  use  the  terra  common  sensibilitv*,  we  can  do  so 
onU'  in  reference  to  touch,  as  it  is  the  sense  that  is  most 
necessar3"  to  animal  existence,  and  as  it  is  enjo3'ed  bv 


* See  Papers  by  tlie  author  in  the  Philosophical  Transactions. 


ORGAN  OF  TOUCH. 


37 


all  animals  from  the  lowest  to  the  highest  in  the 
chain  of  existence. 

While  this  sense  is  distinct  from  the  others,  it  is  the 
most  important  of  all  ; since  through  it  alone  some 
animals  possess  the  consciousness  of  existence  ; and 
to  those  that  enjoy  many  organs  of  sense,  that  of 
touch,  as  we  shall  presently  show,  is  necessary  to  the 
full  developement  of  the  powers  of  all  the  other  organs. 

OF  THE  ORGAN  OF  TOUCH. 

Touch  is  that  peculiar  sensibility  which  gives  the 
consciousness  of  the  resistance  of  external  matter,  and 
makes  us  acquainted  with  the  hardness,  smoothness, 
roughness,  size,  and  form  of  bodies.  It  enables  us  to 
distinguish  what  is  external  from  what  belongs  to  us  ; 
and  while  it  informs  us  of  the  geometrical  qualities  of 
bodies,  we  must  refer  to  this  sense  also  our  judgment 
of  distance,  of  motion,  of  number,  and  of  time. 

Presuming  that  the  sense  of  touch  is  exercised  by 
means  of  a complex  apparatus — by  a combination  of 
the  consciousness  of  the  actioir  of  the  muscles  with  the 
sensibility  of  the  proper  nerves  of  touch,  we  shall,  in 
the  first  place,  examine  in  what  respect  the  organiza- 
tion resembles  that  of  the  other  senses. 

We  have  said  before  that,  oir  the  most  minute  ex- 
aminatioir  of  the  extremity  of  a nerve,  no  appropriate 
structure  can  be  detected  ; and  that  the  nerves  ex- 
panded on  the  organs  of  sense  appear  every  where  the 
same, — soft,  pulpy,  prepared  for  impression,  and  so 
distributed  that  the  impression  shall  reach  them. 
What  is  termed  the  structure  of  the  organs  of  sense, 
is  that  apparatus  by  which  the  external  impression  is 
conveyed  inwards,  and  by  which  its  force  is  concen- 
trated on  the  extremity  of  the  nerve.  The  mechan- 
ism by  which  those  external  organs  are  suited  to  their 
offices,  is  highly  interesting  ; it  serves  to  shew  ( in  a 
way  that  is  level  to  our  comprehension,  as  most  re- 
sembling things  of  human  contrivance)  the  design 
12* 


138 


ORGAN  OF  TOUCH. 


with  which  the  fabric  is  constructed.  Thus,  the  eye 
is  so  seated  and  so  formed  as  to  embrace  the  greatest 
possible  field  of  vision.  TVe  can  understand  the  hap- 
py effects  of  the  convexity  of  the  transparent  cornea, 
t he  influence  of  three  humours  of  various  densities  act- 
ing like  an  achromatic  telescope  ; we  can  admire  the 
precision  with  which  the  rays  of  light  are  concen- 
trated on  the  retina,  and  the  beautiful  provision  for 
enlarging  or  diminishing  the  pencil  of  light,  in  propor- 
tion to  its  intensity  : but  all  this  explains  nothing,  in 
respect  to  the  perception  that  is  excited  in  the  mind 
hy  the  unpulse  on  the  extremity  of  the  nerve. 

In  like  manner,  in  the  complex  apparatus  of  the 
ear,  we  see  how  this  organ  is  fonnedwith  reference 
to  a double  course  of  impressions,  as  they  come 
through  the  solids  or  through  the  body,  and  as  thev 
come  through  the  atmosphere.  We  comprehend  how 
the  undulations  and  vibrations  of  the  air  are  collected 
and  concentrated  ; how  they  are  directed,  throtigh 
the  intricate  passages  of  the  bone,  to  a fluid  in  which 
the  nerve  of  hearing  is  suspended  ; and  we  see  how, 
at  last,  that  nerve  is  moved.  But  we  can  compre- 
hend nothing  more  from  the  study  of  the  external 
organ  of  hearing. 

The  illustration  is  equally  clear  in  reference  to  the 
organ  of  smelling,  or  of  taste.  There  is  nothing  in 
the  nerve  itself,  either  of  the  nose  or  of  the  tongue, 
which  can  explain  why  it  is  susceptible  of  the  parti- 
cular impression.  For  these  reasons,  we  are  prepared 
to  expect  very  little  complexity  in  the  organ  of  touch, 
and  to  believe  that  the  peculiarity  of  the  sense  con- 
sists more  in  the  property  bestowed  on  the  nerve,  than 
in  the  mechanical  adaptation  of  the  exterior  organ. 

OF  THE  CUTICLE. 

The  cuticle  or  epidermis  covers  the  true  skin,  ex- 
cludes the  air,  limits  the  perspiration,  and  in  some  de- 
gi'ee  regulates  the  heat  of  the  body.  It  is  a dead  or 


ORGAN  OP  TOUCH. 


139 


insensible  covering  ; it  guards  from  contact  the  true 
vascular  surface  of  the  skin  ; and  in  this  manner,  it 
off en  prevents  the  communication  of  infection.  We 
aie  most  familiar  with  it  as  that  scarf  skin  which 
scales  off  after  fevers,  or  by  the  use  of  tlie  flesh-brush, 
or  by  the  friction  of  the  clothes  ; for  it  is  continually 
separating  in  thin  scales,  whilst  it  is  as  regularly 
formed  anew  by  the  vascular  surface  below.  The 
condition  of  this  covering  is  intimately  connected  with 
the  organ  of  touch.  The  habit  of  considering  things 
as  produced  accidentally,  has  induced  some  anato- 
mists to  believe  that  the  cuticle  is  formed  by  the  har- 
dening of  the  true  skin.  The  fact,  however,  that  the 
cuticle  is  perfect  in  the  new-born  infant,  and  that 
even  then  it  is  thickest  on  the  hands  and  feet,  should 
liave  shewn  that,  like  every  thing  in  the  animal  struc- 
ture, it  participates  in  the  great  design. 

The  cuticle  is  the  organ  of  touch  in  this  respect, 
that  it  is  the  medium  through  which  the  external 
impression  is  conveyed  to  the  nerves  of  touch  ; and 
the  manner  in  which  this  is  accomplished  is  not  with- 
out interest.  Tire  extremities  of  the  fingers  exhibit 
all  the  provisions  for  the  exercise  of  this  sense.  The 
nails  give  support  to  the  fingers  ; they  are  formed  bi'oad 
and  shield-like,*  in  order  to  sustain  the  elastic  cush- 
ion which  forms  their  extremity  ; and  the  fulness 
and  elasticity  of  the  ends  of  the  fingers  adapt  them 
admirabl)^  for  touch.  But  on  a nearer  inspection,  we 
see  a more  particular  provision  in  the  points  of  the 
fingers.  Wherever  the  sense  of  feeling  is  most  ex- 
quisite, there  are  minute  spiral  ridges  of  cuticle. — 
These  ridges  have,  corresponding  Avith  them,  de- 
pressed lines  on  the  inner  surface  of  the  cuticle  ; and 
these  again  give  lodgement  to  a soft  pulpy  matter, 
in  which  lie  the  extremities  of  the  sentient  nerves. 
There  the  nerves  are  sufficiently  protected,  while  they 
ore  exposed  to  impressions  throrrgh  the  elastic  cuticle. 


* Unguis  scutiformis. 


140 


ORGAN  OF  TOUCH. 


and  thus  give  the  sense  of  touch.  The  organization 
is  simple,  yet  it  is  in  strict  analogy  with  the  other 
organs  of  sense. 

Every  one  must  have  observed  a tendency  in  the 
cuticle  to  become  thickened  and  stronger  by  pressiue 
and  friction.  If  the  pressure  be  partial  and  severe, 
the  action  of  the  true  skin  is  too  much  excited,  fluid 
is  thrown  out,  and  the  cuticle  is  raised  in  a blister. 
If  it  be  still  partial,  but  more  gradually  applied,  a corn 
is  formed.  If,  however,  the  general  surface  of  the 
palms  or  soles  be  exposed  to  pressure,  the  cuticle 
thickens,  until  it  becomes  a defence  like  a glove  or  a 
shoe.  Now,  w'hat  is  most  to  be  admired  in  this  thick- 
ening of  the  cuticle  is,  that  the  sense  of  touch  is  not 
lost,  or  indeed  diminished,  certainly  not  at  all  in  pro- 
portion to  the  protection  afforded  by  the  thickened  skin. 

The  thickened  cuticle  partakes  of  the  structure  of 
the  hoofs  of  animals  : and  we  shall  now  attend  to  the 
nature  of  the  hoof,  as  the  best  possible  illustration  of 
the  manner  in  wliich  the  sensibility  of  the  skin  is  in 
a due  degree  preserved  whilst  the  surface  is  guarded. 

Tlie  human  nail  is  a continuation  of  the  cuticle, 
and  the  hoof  of  an  animal  belongs  to  the  same  class 
of  parts.  In  observing  the  manner  in  which  the 
nerves  enter  the  hoof,  we  have,  in  fact,  a magnified 
view  of  that  which  exists,  but  is  onl}"  more  minute 
and  delicate,  in  the  fingers.  We  may  take  the  horse’s 
foot  as  the  example.  When  the  crust  or  hoof,  which 
is  insensible,  is  separated  from  the  living  part,  we  see 
small  villi  hanging  from  the  vascular  surface,  and 
which  have  been  rvithdrawn  from  the  crust ; looking 
to  the  inside  of  tire  crust,  we  perceive  the  pores  from 
which  these  villi  have  been  pulled.  These  processes 
of  the  living  surface  are  not  merely  extremities  of 
nerves  ; they  consist  of  the  nerves  and  the  necessary 
accompaniments  of  membrane  and  bloodvessels,  on 
a very  minute  scale.  For  it  must  be  remembered 
that  nerves  can  perform  no  function  unless  supplied 
with  blood,  all  qualities  of  life  being  supported  through 


ORGAN  OF  TOUCH. 


14t 


the  circulating  blood.  These  nerves,  so  prolonged 
into  the  hoof,  receive  the  vibrations  of  that  body. 
By  this  means  the  horse  is  sensible  to  the  motion  and 
pressure  of  its  foot,  or  to  its  percussion  against  the 
ground  ; and  without  this  provision,  there  would  be  a 
certain  imperfection  in  the  limb. 

In  a former  part  of  this  treatise  I have  shewn  by 
what  curious  mechanism  the  horse’s  foot  is  made 
yielding  and  elastic,  for  the  purpose  of  bearing  the 
percussion  against  the  ground.  But  in  made  roads, 
and  with  the  imperfections  of  shoeing,  the  pressure 
and  concussion  are  too  severe  and  too  incessant ; so 
that  the  protecting  sensibility  of  the  foot  is  converted 
into  a source  of  pain  from  the  iirflammation  which 
arises,  and  the  horse  is  thus  “ foundered.”  There  is 
a remedy  for  this  condition  in  dividing  the  nerve ; 
the  consequence  of  which  operation  is,  that  the  horse, 
instead  of  moving  with  timid  steps,  puts  out  his  feet 
freely,  and  the  lameness  is  cured.  If,  however,  we 
were  to  receive  the  statement  thus  barely,  the  fact 
would  militate  against  our  conclusion  that  mechani- 
cal provision  and  sensibility  go  together,  being  equal- 
ly necessary  to  the  perfection  of  the  instrument.  We 
must  take  into  consideration  this  leading  fact,  that 
pressure  against  the  sole  and  crust  is  necessary  to  the 
play  of  the  foot  and  to  its  perfection.  When  this 
part  becomes  inflamed,  the  animal  does  not  put  its 
foot  freely  down,  nor  does  it  bear  its  weight  upon  the 
hoof  so  as  to  bring  all  the  parts  into  action ; hence  con- 
traction is  prodirced,  the  most  common  defect  of  the 
horse’s  hoof.  When  the  animal  is  relieved  from  pain 
by  the  division  of  the  nerve,  it  uses  the  foot  freely,  and 
use  restores  all  the  natural  actions  of  this  fine  piece  of 
mechanism.  It  is  obvious,  however,  that  there  is  a 
certain  defect ; the  horse  has  lost  his  natural  protection, 
and  must  now  be  indebted  to  the  care  of  his  rider.  It 
has  not  only  lost  the  pain  which  should  guard  against 
over  exertion,  but  the  feeling  of  the  ground,  which  is 
necessary  to  his  being  perfectly  safe  as  a roadster. 


142 


ORGAN  OF  TOUCH. 


The  teeth  are  provided  with  sensibility  much  in 
the  same  manner  as  the  hoof  of  the  horse  is ; for 
altliough  the  bone  and  enamel  have  no  sensibility, 
yet  a branch  of  a sensible  nerve  (the  fifth)  enters 
into  the  cavity  of  every  tooth,  and  the  vibration  being 
communicated  through  the  tooth  to  the  nerve,  the 
smallest  grain  is  felt  between  the  teeth. 

But,  to  return  to  the  human  hand ; in  the  fingers 
and  palm  of  a man  who  uses  the  fore-hammer,  the 
cuticle  is  thickened  in  a remarkable  manner  ; the 
lines,  however,  become  deeper,  and  the  villi  longer  ; 
which,  joined  to  the  aptitude  of  the  cuticle  to  convey 
the  impression  to  those  included  nerves,  leaves  him 
in  possession  of  the  sense  of  touch  in  a very  high 
degree. 

In  the  foot  of  the  ostrich  we  may  have  a magni- 
fied view  of  the  thickened  cuticle  and  the  lengthened 
nerves.  The  outer  skin  ahnost  equals  in  thickness 
the  hoof  of  the  solidungula,  and  when  it  is  separated 
from  the  sensible  sole,  the  villi,  or  papillae,  having  in 
them  the  sensible  nerves,  are  withdrawn,  leaving  cor- 
responding foramina  or  pores  in  the  sole.  We  per- 
ceive that  if  the  object  had  been  merely  to  cover 
and  protect  the  foot,  it  would  have  been  sufficient  to 
have  invested  it  with  a succession  of  solid  and  dead 
layers  of  cuticle.  This  would  have  been  the  case 
had  the  cuticle  been  merely  thickened  by  pressure, 
and  had  there  been  no  design  to  make  a provision 
adapted  in  all  respects  to  the  habits  of  the  bird. 

Such,  then,  is  the  structure  of  tlie  organ  of  touch  ; 
obvious  in  the  extremities  of  the  fingers  ; magnified 
in  the  foot  of  the  horse  or  of  the  ostrich  ; and  exist- 
ing even  in  the  delicate  skin  of  the  lips. 

I have  casually  noticed  that  increased  vascularity 
is  always  an  accompaniment  of  nerves,  and  neces- 
sary to  the  sensibility  of  a part.  In  the  museum  of 
the  College  of  Surgeons  we  see  that  Mr.  Hunter  had 
taken  the  pains  to  demonstrate  this,  by  the  injection 
of  the  bloodvessels  of  a slug.  Although  fluid  was 


ORGAN  OF  TOUCH. 


143 


injected  from  its  heart,  the  blush  from  the  vermilion 
extends  over  its  foot  ; the  foot,  in  these  gasteropoda, 
being  the  whole  lower  flat  surface  on  which  the  ani- 
mal creeps.  This  surface  is  also  the  organ  of  touch, 
by  which  it  feels  and  directs  its  motions.  It  is  on  the 
same  principle,  if  we  may  compare  such  things,  that 
we  explain  the  rosy-tipped  fingers  and  the  ruby  lips, 
which  imply  fine  sensibility  combined  with  high 
vascularity. 

Having  described  the  relation  of  the  cuticle  to  the 
nerves  of  touch,  we  may  take  notice  of  another  qua- 
lity, in  its  roughness,  and  of  the  advantages  accruing 
from  this.  In  the  first  place,  as  to  the  subserviency 
of  this  quality  to  feeling,  we  must  be  sensible  that  in 
touching  a finely  polished  surface  the  organ  is  but 
imperfectly  exercised,  as  compared  with  its  condition 
when  we  touch  or  grasp  a rough  and  irregular  body. 
Had  the  cuticle  been  finely  polished  on  its  surface  it 
would  have  been  but  ill  suited  to  touch  : but,  on  the 
contrary,  it  has  a very  peculiar  roughness  which 
adapts  it  to  feeling.  A provision  for  friction,  as  op- 
posed to  smoothness,  is  a necessary  quality  of  some 
parts  of  the  skin.  The  roughness  of  the  cuticle  has 
the  advantage  of  giving  us  a firmer  grasp,  and  a 
steadier  footing.  Nothing  is  so  little  apt  to  slip  as 
the  thickened  cuticle  of  the  hand  or  foot.  In  the 
hoofs  of  animals,  as  might  be  expected,  this  structure 
is  further  developed.  The  chamois  or  goat  steps 
securely  on  the  ledges  of  rocks  and  at  great  heights, 
where  it  would  seem  impossible  to  cling.  On  the 
pads  or  cushions  of  the  cat,  the  cuticle  is  rough  and 
granular  ; and  in  the  foot  of  the  squirrel,  indeed  of 
all  animals  which  climb,  those  pads  covered  with  the 
peculiar  texture  of  the  cuticle,  give  security  in  de- 
scending, as  their  claws  enable  them  to  climb. 

In  concluding  this  section,  we  perceive  that  the 
organ  of  touch  consists  of  nerves  appropriated  to  re- 
ceive the  impressions  of  bodies  capable  of  afibrding 
resistance.  Fine  filaments  of  those  nerves,  wrapt  up 


144 


ORGAN  OF  TOUCH. 


iu  delicate  membrane  with  their  accompanying  arte- 
ries and  veins,  project  from  the  true  skin  into  corres- 
ponding grooves  or  foramina  of  the  cuticle.  They  are 
not  absolutely  in  contact  with  the  cuticle,  but  are 
surrounded  with  a semi-fluid  matter.  By  this  fluid 
and  by  the  cuticle  they  are  protected,  at  the  same 
time  that  they  are  sensible  to  the  pressure  made  on 
the  surface,  and  to  cutting,  pricking,  and  heat."*" 
But  this  capacity,  we  repeat,  is  not  owdng,  strictly 
spealdng,  to  any  thing  in  the  structure  of  the  organ, 
but  to  the  appropriation  of  the  nerves  to  this  class  of 
sensations. 

* It  is  a curious  confirmation  of  tlie  fact,  that  the  cutaneous  nei-ve 
is  adapted  to  receive  impressions  from  the  varieties  of  temperature, 
that  when  disease  takes  place  in  the  centre  of  the  trunk  of  a nerve, 
or  when  the  nerve  is  surrounded  with  diseased  parts,  the  sensation  of 
burning  accompanies  the  pain ; and  the  patient  refers  this  to  the  part 
of  the  skin  to  which  the  extreme  branch  of  the  nerve  is  distributed. 
By  a burning  sensation  in  the  sole  of  the  foot,  I have  been  directed  to 
the  disease  seated  in  the  centre  of  the  thigh. 


CHAPTER  IX. 


OF  THE  MUSCULAR  SENSE. 

Of  the  Sensibility  of  the  Infant  to  Impressions,  and  the 
gradual  improvement  of  the  Sense  of  Touch. 

A NOTION  prevails  that  the  young  of  animals  are 
directed  by  instinct,  but  that  there  is  an  exception  in 
regard  to  the  human  offspring : that  in  tlie  child  we  have 
to  trace  the  gradual  dawn  and  progressive  improve- 
ment of  reason.  This  is  not  quite  true  ; we  doubt 
whether  the  body  would  ever  be  exercised  under  the 
influence  of  reason  alone,  and  if  it  were  not  fii'st  di- 
rected by  sensibility  which  are  innate  or  instinctive. 

Tire  sensibilities  and  the  motions  of  the  lips  and 
tongue  are  perfect  from  the  beginning  : and  the  dread 
of  falling  is  shewn  in  the  young  infant  long  before  it 
can  have  had  experience  of  violence  of  any  kind. 

The  hand,  which  is  to  become  the  instrument  for 
perfecting  the  other  senses  and  developing  the  endow- 
ments of  the  mind  itself,  is  in  the  infant  absolutely  pow- 
erless. Pain  is  poetically  described  as  that  power  into 
whose  “ iron  grasp”  we  are  consigned,  to  be  introdu- 
ced to  a material  world  ; now,  although  the  infant  is 
capable  of  an  expression  of  pain,  which  cannot  be  mis- 
understood and  is  the  same  which  accompanies  all 
painful  impressions  during  the  v/hole  life,  yet  it  is  un- 
conscious of  the  part  of  the  body  which  suffers.  We 
have  again  recourse  to  the  surgeon’s  experience. 
There  occur  certain  congenital  imperfections  which 
require  an  operation  at  this  early  stage  of  life  ; but 
the  infant  makes  no  direct  effort  with  its  hand  to  repel 
the  instrument,  or  to  disturb  the  dressing,  as  it  will 
at  a period  somewhat  later. 

13 


146 


OF  THE  MUSCULAR  SENSE. 


The  lips  and  tongue  are  first  exercised  ; the  next 
motion  is  to  put  the  hand  to  the  moutli,  in  order  to 
suck  it  : and  no  sooner  are  the  fingers  capable  of 
grasping,  than  whatever  they  hold  is  canied  to  the 
mouth.  So  that  the  sensibility  to  touch  in  the  lips 
and  tongue,  and  their  motions,  are  the  first  inlets  to 
knowledge  ; and  the  use  of  the  hand  is  a later  ac- 
quirement. 

The  knowledge  of  external  bodies  as  distinguished 
from  ourselves,  cannot  be  acquired  until  the  organs  of 
touch  in  the  hand  have  become  famihar  with  our  own 
lunbs  ; we  cannot  be  supposed  capable  of  exploring 
any  thing  by  the  motion  of  the  hand,  or  of  judging 
of  the  form  or  tangible  qualities  of  an  object  pressed 
against  the  skin,  before  we  have  a knowledge  of  our 
own  body  as  distinguished  from  things  external  to  us. 

The  first  office  of  the  hand,  then,  is  to  exercise  the 
sensibility  of  the  mouth  ; and  the  infant  as  certainly 
questions  the  reality  of  things  bj'  that  test,  as  the  dog 
does  by  its  acute  sense  of  smelling.  In  the  infant, 
the  sense  of  the  lips  and  tongue  is  resigned  only  in 
favour  of  the  sense  of  vision,  when  that  sense  has  im- 
proved and  offers  a greater  gratification,  and  a better 
means  of  judging  of  the  qualities  of  lx)dies.  The 
hand  very  slowly  acquires  the  sense  of  touch,  and 
many  ineffectual  efforts  are  seen  in  the  arms  and 
fingers  of  the  child  before  the  direction  of  objects  or 
their  distance  is  ascertained.  Gradually  the  length 
of  the  arm,  and  the  extent  of  its  motions  become  the 
measure  of  distance,  of  form,  of  relation,  and  perhaps 
of  time. 

Next  in  importance  to  the  sensibility  of  the  mouth, 
we  may  contemplate  that  sense  which  is  early  exhi- 
bited in  the  infant, — the  terror  of  falling.  The  nurse 
will  tell  us  that  the  infant  lies  composed  while  she 
carries  it  in  her  amis  up  stairs  ; but  that  it  is  agitated 
in  carrying  it  down.  If  an  infant  be  laid  upon  the 
arms  and  dandled  up  and  dowm,  its  body  and  limbs 
will  be  at  rest,  whilst  it  is  raised ; but  they  will  strug- 


OF  THE  MUSCULAR  SENSE. 


147 


gle  and  make  an  effort  as  it  descends.  There  is  here 
the  indication  of  a sense,  an  innate  feeling  of  danger, 
the  influence  of  which  we  may  perceive  when  the 
child  first  attempts  to  stand  or  run.  When  the  child 
is  set  upon  its  feet,  and  the  nurse’s  arms  fonn  a hoop 
around  it  without  touching  it,  it  slowly  learns  to  ba- 
lance itself  and  stand ; but  under  a considerable  ap- 
prehension. Presently,  it  will  stand  at  such  a dis- 
tance from  the  nmse’s  knee,  that  if  it  should  lose  its 
balance,  it  can  throw  itself  for  protection  into  her  lap. 
In  these  its  first  attempts  to  use  its  muscular  frame, 
it  is  directed  by  an  apprehension  which  cannot  as  yet 
be  attributed  to  experience.  By  degrees  it  acquires 
the  knowledge  of  the  measure  of  its  arm,  the  relative 
distance  to  which  it  can  reach,  and  the  power  of  its 
muscles.  Children,  therefore,  are  cowardly  by  in- 
stinct : they  show  an  apprehension  of  falling ; and  we 
may  gradually  trace  the  efforts  which  they  make,  under 
the  guidance  of  this  sensibility,  to  perfect  the  mus- 
cular sense.  In  the  mean  time,  we  perceive  how  in- 
stinct and  reason  are  combined  hr  early  infancy  : how 
necessary  the  first  is  to  existence  ; how  it  is  subser- 
vient to  reason  : and  how  it  yields  to  the  progress  of 
reason,  until  it  becomes  so  obscured  that  we  can 
hardly  discern  its  influence. 

When  treating  of  the  senses,  and  showing  hoAV  one 
organ  profits  by  the  exercise  of  the  other,  and  how 
each  is  indebted  to  that  of  touch,  1 was  led  to  observe 
that  the  sensibility  of  the  skin  is  the  most  dependant 
of  all  on  the  exercise  of  another  quality.  Without  a 
sense  of  muscular  action  or  a consciousness  of  the  de- 
gree of  effort  made,  the  proper  sense  of  touch  could 
hardly  be  an  inlet  to  knowledge  at  all.  I am  now  to 
show  that  the  motion  of  the  hand  and  fingers,  and 
the  sense  or  consciousness  of  their  action,  must  be 
combined  with  the  sense  of  touch,  properly  so  called, 
before  Ave  can  ascribe  to  it  the  influence  which  it 
possesses  over  the  other  organs. 

In  my  general  course  of  lectures  on  anatomy,  I 


148 


OF  THE  MUSCULAR  SENSE. 


ventured  on  this  explanation  from  the  commence- 
ment ; much  doubting,  however,  the  coirectness  of 
my  reasoning,  from  seeing  that  the  great  authorities 
on  this  subject  made  no  account  of  the  knowledge 
derived  from  the  motions  of  our  own  frame.  I called 
this  consciousness  of  muscular  exertion  a sixth  sense  ; 
considering  it  as  essential  to  the  exercise  of  the  sense 
of  touch.  I can  now  refer,  in  confirmation  of  this 
view,  to  the  works  of  philosophers  who  have  been 
educated  to  medicine  ; and  to  whom  the  necessity  of 
the  combination  of  the  two  faculties  had  suggested 
itself  as  it  had  to  me.*  Those  distinctions  were  con- 
nected with  my  enquiries  into  the  functions  of  the 
nervous  system,  and  in  some  measure  directed 
them.f 

The  Abbe  Nollet,  after  extolling  the  sense  of  touch 
as  superior  to  all  the  other  senses,  and  as  deserving 


* See  Dr.  Brown’s  Lectures  on  Moral  Philosophy, 
t It  was  tlris  conviction — that  we  are  sensible  of  the  action  of  the 
muscles,  which  led  me  to  the  investigation  of  their  nerves  ; first,  by 
anatomv,  and  then  by  experiment.  I was  finally  enabled  to  show 
that  the  muscles  had  two  classes  of  neires — that  on  exciting  one  of 
these,  the  muscle  contracted  ; that  on  exciting  the  other,  no  action 
took  place.  The  nen'e  which  had  no  power  was  found  to  be  a nerve 
of  sensation  : and  thus,  it  rvas  proved  that  tliere  is  a nervous  circle 
connecting  the  muscles  with  the  brain  : that  one  nerve  is  not  capable 
of  transmitting  what  is  called  the  nervous  spirits,  in  two  diiferent 
directions  at  one  instant  of  time ; but  that  for  the  regulation  of  tlie 
muscles,  there  is  a nerve  of  sensibility  to  convey  the  nervous  influence 
from  the  muscles  towards  the  sensorium,  as  well  as  a nerve  of  action 
for  conveying  the  mandate  of  the  will  to  the  muscles.  In  their  dis- 
tribution through  the  body,  the  nerves  wlflch  possess  these  two  di^ 
tinct  powers  are  wrapped  up,  or,  as  it  were,  woven  together  in  the 
same  sheath  ; and  they  present  to  the  eye  tlie  appearance  of  one 
neri^e.  It  was  only  by  examining  the  nerves  at  fiieir  roots,  that  is, 
where  they  arise  from  different  tracts  of  the  brain  and  spinal  mar- 
row, and  before  they  have  coalesced,  that  I succeeded  in  demonstrat- 
ing their  distinct  functions.  In  the  face,  the  neri'e  of  motion  pa^es 
by  a circuitous  course,  apart  from  the  nerve  of  sensation,  to  be  dis- 
tributed  in  the  muscles  ; and  therefore  the  distinct  characters  of  these 
nerves  were  more  easily  proved  b}'  experiment  than  in  mv  oUier 
part  of  the  bod v.  See  the  Philosophical  Transacuons  on  the  JN  er- 
vous  Circle  which  connects  the  Voluntary  INIuscles  with  the  Brain,  ’ 
and  the  “ Nervous  System.”  4to.  Longman, 


OF  THE  MUSCULAR  SENSE. 


149 


to  be  considered  the  genus  under  which  the  others 
should  be  included  as  subordinate  species,  makes  this 
remark — “ Besides,  it  has  this  advantage  over  them, 
“ to  be  at  the  same  time  both  active  and  passive  ; for  it 
“ not  only  puts  it  in  our  power  to  judge  of  what  makes 
“ an  impression  upon  us,  but  likewise  of  what  resists 
“ our  impulsions.”  The  mistake  here  lies  in  giving 
to  the  nerves  of  touch  a property  which  must  belong 
to  the  actions  of  muscles.  So  it  is  affirmed  by  phy- 
siologists, as  I have  already  had  occasion  to  state, 
that  the  sense  of  touch  differs  from  the  other  senses 
by  this  circumstance — that  an  effort  is  propagated 
towards  it,  as  well  as  a sensation  received  from  it. 
This  confusion  obviously  arises  from  considering  the 
muscular  agency,  which  is  directed  by  the  will  dur- 
ing the  exercise  of  touch,  as  belonging  to  the  nerve 
of  touch  properly.  We  proceed  to  show  how  the 
sense  of  motion  and  that  of  touch  are  necessarily 
combined. 

When  a blind  man,  or  a man  with  his  eyes  shut, 
stands  upright,  neither  leaning  upon,  nor  touching 
aught ; by  what  means  is  it  that  he  maintains  the 
erect  position  'I  The  symmetry  of  his  body  is  not  the 
cause ; the  statue  of  the  finest  proportion  must  be 
soldered  to  its  pedestal,  or  the  wind  will  cast  it  down. 
How  is  it,  then,  that  a man  sustains  the  perpendicu- 
lar posture,  or  inclines  in  due  degree  towards  the 
winds  that  blow  upon  him  ? It  is  obvious  that  he 
has  a sense  b)’’  which  he  knows  the  inclination  of  his 
body,  and  that  he  has  a ready  aptitude  to  adjust  it, 
and  to  correct  any  deviation  from  the  perpendicular. 
What  sense  then  is  this  1 for  he  touches  nothing,  and 
sees  nothing  ; there  is  no  organ  of  sense  hitherto  ob- 
served which  can  serve  him,  or  in  any  degree  aid  him. 
Is  it  not  that  sense  which  is  exhibited  so  early  in  the 
infant,  in  the  fear  of  falling  1 Is  it  not  the  full  de- 
velopement  of  that  property  which  was  early  shown 
in  the  straggle  of  the  infant  while  it  )mt  lay  in  the 
nurse’s  arms  ] It  can  only  be  by  the  adjustment  of 


ISO 


OF  THE  MUSCULAR  SENSE, 


muscles  that  the  limbs  are  stiflfened,  the  body  firmly 
balanced  and  kept  erect.  There  is  no  other  source 
of  knowledge,  but  a sense  of  the  degree  of  exertion  in 
his  muscular  frame,  by  which  a man  can  know  the 
position  of  his  body  and  limbs,  while  he  has  no  point 
of  vision  to  direct  his  efforts,  or  the  contact  of  any  ex- 
ternal body.  In  truth,  we  stand  by  so  fine  an  exer- 
cise of  this  power,  and  the  muscles  are,  from  habit, 
directed  with  so  much  precision  and  with  an  effort  so 
slight,  that  we  do  not  know  how  we  stand.  But  if 
we  attempt  to  walk  on  a narrow  ledge,  or  stand  in  a 
situation  where  we  are  in  danger  of  falling,  or  rest  on 
one  foot,  we  become  then  subject  to  apprehension : the 
actions  of  the  muscles  are,  as  it  were,  magnified  and 
demonstrative  of  t he  degree  in  which  they  are  excited. 

We  are  sensible  of  the  position  of  our  limbs  ; we 
know  that  the  arms  hang  by  the  sides  ; or  that  they 
are  raised  and  held  out ; although  we  touch  nothing 
and  see  nothing.  It  must  be  a propert_y  internal  to 
the  frame  by  which  Ave  knoAV  this  position  of  the 
members  of  our  body  : and  what  can  this  be  but  a 
consciousness  of  the  degree  of  action  and  the  adjust- 
ment of  the  muscles  I At  one  time,  I entertained  a 
doubt  whether  this  proceeded  from  a knowledge  of 
the  condition  of  the  muscles  or  from  a consciousness 
of  the  degree  of  effort  which  Avas  directed  to  them  in 
volition.  It  was  A\nthavieAV  to  elucidate  this,  that  I 
made  the  observations  Avhich  terminated  in  the  dis- 
coA^ery  that  CA^ery  muscle  had  tAvo  nerves — one  for 
sensation,  and  one  to  conve}^  the  mandate  of  the  AA'ill 
and  direct  its  action.  I had  reasoned  in  this  mamier — 
Ave  aAvake  Avitli  a knoAAdedge  of  the  position  of  our 
limbs  : this  cannot  be  from  a recollection  of  the  ac- 
tion AAdiich  placed  them  Avhere  they  are  ; it  must, 
therefore,  be  a consciousness  of  their  present  condition. 
When  a person  in  these  circumstances  moves,  he  has 
a determined  object ; and  he  must  be  conscious  of  a 
previous  condition  before  he  can  desire  a change  or 
direct  a movement. 


OF  THE  MUSCULAR  SENSE. 


151 


After  a limb  has  been  removed  by  the  surgeon,  the 
person  still  feels  pain,  and  heat,  and  cold  in  it.  Urg- 
ing a patient  to  remove  who  has  lost  his  limb,  I 
have  seen  him  catch  at  the  limb  to  guard  it,  forgetful 
that  it  was  removed  ; and  long  after  his  loss,  he 
experiences  a sensation  not  only  as  if  the  limb  remain- 
ed, but  as  if  it  were  placed  or  hanging  in  a particular 
position  or  posture.  I have  asked  a patient — “ Where 
do  you  feel  your  arm  now]”  and  he  has  said,  “ I feel  it 
“ as  if  it  lay  across  my  breast,”  or  that  it  is  “ lying 
“ by  my  side.”  It  seems  also  to  change  with  the 
change  of  posture  of  the  body.  These  are  additional 
proofs  of  a muscular  sense  ; that  there  is  an  internal 
sensibility  corresponding  with  the  changing  condition 
of  the  muscles ; and  that  as  the  sensations  of  an 
organ  of  sense  remain  after  the  destruction  of  tire 
outward  organ,  so  here  a deceptions  sensibility  to  the 
condition  of  the  muscles,  as  well  as  to  the  condition 
of  the  skin,  is  felt  after  the  removal  of  the  limb. 

By  such  arguments  I have  been  in  the  habit  of 
showing  that  we  possess  a muscular  sense,  and  that 
without  it  we  could  have  no  guidance  of  the  frame. 
We  could  not  command  our  muscles  in  standing,  far 
less  in  walking,  leaping,  or  running,  had  we  not  a 
perception  of  the  condition  of  the  muscles  previous  to 
the  exercise  of  the  will.  And  as  for  the  hand,  it  is 
not  more  the  freedom  of  its  action  which  constitutes 
its  perfection,  than  the  knowledge  which  we  have  of 
these  motions,  and  our  consequent  ability  to  direct  it 
with  the  utmost  precision. 

The  necessity  for  the  combination  of  two  distinct 
properties  of  the  nervous  system  in  the  sense  of  touch 
becomes  more  obvious  if  we  examine  their  operation 
in  another  but  analogous  organ  ; for  example,  in  the 
palpa  or  tentacula  of  the  lower  animals.  These  ani- 
mals use  those  instruments  to  grope  their  way  : and 
they  consist  of  a rigid  tube  containing  a pulpy  mat- 
ter, in  which  there  is  a branch  of  nerve  that  possesses 
in  an  exquisite  degree  the  sense  of  touch.  Now  when 


152 


OF  THE  MUSCULAR  SENSE. 


this  instrument  touches  a body  and  the  vibration  runs 
along  the  pulp  of  the  nerve,  the  animal  can  be  sensi- 
ble only  of  an  obstruction  ; but  where  is  that  obstruc- 
tion, and  how  is  the  creature’s  progress  to  be  directed 
to  avoid  it?  We  must  acknowledge  that  the  instru- 
ment moves  about  and  feels  on  all  sides,  and  that  it 
is  the  action  of  the  muscles  moving  this  projecting 
instrument,  and  the  sense  of  their  activity,  which 
conve}^  the  knowledge  of  the  place  or  direction  of  the 
obstructing  body.  It  appears,  therefore,  that  even  in 
the  very  lowest  creatures  the  sense  of  touch  implies 
the  comparison  of  two  distinct  senses. 

^ That  insects  have  the  most  exquisite  organs  of 
sense  must  be  allowed  : but  we  do  not  reflect  on  the 
extraordinary  accuracy  with  which  the)'  measure  dis- 
tance ; which  is  an  adaptation  of  the  muscular  exer- 
tion to  the  sense  of  vision.  The  spider  which  I have 
already  alluded  to  in  a former  chapter — the  aranea 
scenica,  when  about  to  leap,  elevates  itself  upon  its 
fore  legs,  and  lifting  its  head,  seems  to  survey  the 
spot  before  it  jumps.  When  this  insect  spies  a small 
gnat  or  fly  upon  the  wall,  it  creeps  verv  gently 
towards  it,  with  short  steps,  till  it  comes  within  a pro- 
per distance,  and  then  it  springs  suddenly  like  a tiger. 
It  will  jump  two  feet  to  seize  upon  a bee.* 

We  have  a more  curious  instance  of  the  precision 
of  eye  and  the  adaptation  of  muscular  action  in  the 
chcetodon  rostrahis.'f  This  fish  inhabits  the  Indian 
rivers,  and  lives  on  the  smaller  aquatic  flies.  When 
it  observes  a fly  alighted  on  a twig  or  fl)'ing  near  (for 
it  can  shoot  them  on  the  wing)  it  darts  a drop  of 
water  with  so  steady  an  aim  as  to  bring  the  fly  down 
into  the  water,  when  it  falls  an  easy  prey.  These 
fishes  are  kept  in  large  vases  for  amusement,  and  if 
a fly  be  presented  on  the  end  of  a twig,  they  will 
shoot  at  it  with  surprising  accuracy.  In  its  natural 
state  it  will  hit  a fly  at  the  distance  of  from  three  to 


Kirby,  f ChoDtodon,  a genus  of  tlie  Acanthopterygii. 


OF  THE  MUSCULAR  SENSE, 


153 


six  feet.  The  zeus  insidiator*  has  also  the  power  of 
forming  its  mouth  into  a tube  and  squirting  at  flies  so 
as  to  encumber  their  wings  and  bring  them  to  the 
surface  of  the  water.  Whether  led  to  admire  the 
wonderful  power  of  instinct  in  these  inferior  crea- 
tures, or  the  property  acquired  by  our  own  eye,  we 
must  acknowledge  a compound  operation. f 

The  impression  of  odours  on  the  nerve  of  smelling 
is  exactly  what  some  would  have  us  to  believe  the 
effect  of  light  is  on  the  nerve  of  vision  ; and  }'^et, 
that  impression  on  the  nerve  of  vision  is  sufficient,  in 
their  opinion,  to  inform  us  of  all  that  we  know 
through  the  eye.  Now  of  the  direction  and  distance 
from  whicli  odours  come,  we  are  quite  ignorant,  until 
by  turning  the  head  and  directing  the  nostrils,  and 
moving  this  way  and  that,  we  make  comparison,  and 
discover  on  which  side  the  smell  is  strongest  on  the 
sense.  We  can  judge  of  the  direction  of  sounds 
without  turning  the  head,  because  the  strength  of 
vibration  is  unequal  on  the  two  sides  of  the  head,  and 
a comparison  is  made  of  the  two  impressions.  But 
when  a person  is  deaf  of  one  ear  the  operation  is 
difficult ; he  is  often  mistaken  as  to  the  direction  of 
sounds,  and  he  has  more  necessity  to  turn  the  head 
and  to  compare  the  position  of  the  tube  of  the  ear 
with  the  strength  of  the  impressions.  Accordingly, 
in  mixed  company,  where  there  are  many  speakers, 
he  appears  positively  deaf,  from  the  impossibility  of 
distinguishing  minutely  the  direction  of  sounds. 

The  last  proof  of  the  necessity  of  the  combination 
of  the  muscular  sense  with  the  sense  of  contact  will 
be  conclusive.  The  following  is  not  a solitary  in- 
stance : — ■ 

A mother  while  nursing  her  infant  was  seized  Avith 

+ Belonging  to  another  genus  of  the  same  Order. 

t In  these  instances  a difficulty  will  readily  occur  to  the  reader; 
how  does  the  fish  judge  of  position,  since  the  rays  of  light  are  refract- 
ed at  the  surface  of  the  water?  Does  instinct  enable  it  to  do  this^ 
or  ia  it  bv  experience  ? 


154 


OF  THE  MUSCULAR  SENSE. 


a paralysis,  attended  by  the  loss  of  power  on  one  side 
of  her  body,  and  the  loss  of  sensibility  on  the  other- 
side.  The  surprising,  and,  indeed,  the  alarming  cir- 
cumstance here  was,  that  she  could  hold  her  child 
to  her  bosom  with  the  arm  wlricli  possessed  muscular 
power,  but  only  as  long  as  she  looked  at  the  infant. 
If  surrounding  objects  withdrew  her  attention  from 
the  state  of  her  arm,  the  flexor  muscles  gradually 
relaxed  and  the  child  was  in  danger  of  falling.  The 
details  of  the  case  do  not  beloirg  to  our  present  en- 
quiry ; but  we  see  here,  first,  that  there  are  two  pro- 
perties in  the  arm ; which  is  shown  by  the  loss  of 
the  one  and  the  contmuance  of  the  other  ; secondly, 
that  these  properties  exist  through  different  conditions 
of  the  nervous  s)’-stem ; and,  thirdly,  we  perceive 
how  ineffectual  to  the  exercise  of  the  limbs  is  the 
continuance  of  the  muscular  power,  without  the 
sensibility  which  should  accompany  and  direct  it. 

The  property  in  the  hand  of  ascertaining  the  dis- 
tance, the  size,  the  weight,  the  form,  the  hardness 
and  softness,  the  roughness  or  smoothness  of  objects 
residts  from  the  combined  perception — through  the 
sensibility  of  the  proper  organ  of  touch  and  the  mo- 
tion of  the  arm,  hand,  and  fingers.  But  the  motion 
of  the  fingers  is  especially  necessarj^  to  the  sense  of 
touch  ; they  bend,  extend,  or  expand,  moving  in  all 
directions  like  palpa,  with  the  advantage  of  embrac- 
ing the  object,  and  feeling  it  on  all  its  surfaces  ; sen- 
sible to  its  solidity  and  to  its  resistance  when  grasped  ; 
moving  round  it  and  gliding  over  its  surface,  and, 
therefore,  feeling  every  asperity. 

THE  PLEASURES  ARISING  FROM  THE  MUSCULAR  SENSE. 

The  exercise  of  the  muscular  frame  is  the  som'ce  of 
much  of  the  knowledge  which  is  usually  supposed  to 
be  obtained  through  the  organs  of  sense  ; and  to  this 
source,  also,  we  must  trace  some  of  our  chief  enjoy- 
ments. We  may,  indeed,  affirm  that  it  is  benevolently 


OF  THE  MUSCULAR  SENSE. 


155 


provided  that  vigorous  circulation,  and,  therefore,  the 
healthful  condition  both  of  the  mind  and  the  body, 
shall  result  from  muscular  exertion  and  the  alterna- 
tion of  activity  and  repose. 

The  pleasure  which  arises  from  the  activit)^  of  the 
body  is  also  attended  by  gratification  from  the  exer- 
cise of  a species  of  power — as  in  mere  dexterity,  suc- 
cessful pursuit  in  the  field,  or  the  accomplishment  of 
some  work  of  art.  This  activity  is  followed  by  weari- 
ness and  a desire  for  rest,  and  although  unattended 
with  any  describable  pleasure  or  local  sensation,  there 
is  diffused  through  eveiy  part  of  the  frame,  after 
fatigue  and  whilst  the  active  powers  are  sinking 
into  repose,  a feeling  almost  voluptuous.  To  this 
succeeds  the  impatience  of  rest,  and  thus  we  are  urg- 
ed to  the  alternations  which  are  necessary  to  health, 
and  invited  on  from  stage  to  stage  of  our  existence. 

We  owe  other  enjoyments  to  the  muscular  sense. 
It  would  appear  that  in  modern  times  we  know  com- 
paratively little  of  the  pleasures  arising  from  motion. 
The  Greeks,  and  even  the  Romans,  studied  elegance 
of  attitude  and  movement.  Their  apparel  admitted 
of  it,  and  their  exercises  and  games  must  have  led  to 
it.  Their  dances  were  not  the  result  of  mere  exuber- 
ance of  spirits  and  activity  ; they  studied  harmony  in 
the  )uotion  of  the  body  and  limbs,  and  majesty  of  gait. 
Their  dances  consisted  more  of  the  unfolding  of  the 
arms  than  of  the  play  of  the  feet, — “Their  arms  sub- 
lime that  floated  on  the  air.”  The  Pyrrhic  dances 
were  elegant  movements,  joined  to  the  attitudes  of 
combat,  and  performed  in  correct  coincidence  with 
the  expression  of  the  music.  The  spectators  in  their 
theatres  must  have  had  very  different  associations 
from  ours,  to  account  for  the  national  enthusiasm 
arising  from  music  and  their  rage  excited  by  a mere 
error  in  the  time. 

This  reminds  us  that  the  divisions  in  music  in  some 
degree  belong  to  the  muscular  sense.  A man  will 
put  down  his  staff  in  regulated  time,  and  the  sound  of 


156 


OF  THE  MUSCULAR  SENSE. 


his  steps  will  fall  into  a measure,  in  his  common  walk. 
A boy  striking  the  railing  in  mere  wantonness,  will 
do  it  with  a regular  succession  of  blows.  This  disposi- 
tion of  the  muscular  frame  to  put  itself  into  motion 
with  an  accordance  to  time  is  the  source  of  much  that 
is  pleasing  in  music,  and  aids  the  effect  of  melod}^ 
There  is  thus  established  the  closest  connection  be- 
tween the  enioyments  of  the  sense  of  hearing  and  the 
exercise  of  the  muscular  sense.* 

* To  leam  how  much  the  enjoyment  of  the  sense  of  vision  belongs 
£0  motion,  see  the  “ Additional  Illustrations,”  at  the  end  of  the  volume. 


CHAPTER  X. 


THE  HAND  NOT  THE  SOURCE  OF  INGENUITY  OR  CON- 
TRIVANCE, NOR  CONSEQUENTLY  OP  MAN’s  SUPE- 
RIORITY. 

Seeing  the  perfection  of  the  hand,  we  can  hardly 
be  surprised  that  some  philosophers  should  have  en- 
tertained the  opinion  with  Anaxag-oras,  that  the  supe- 
riority of  man  is  owing  to  his  hand.  We  have  seen 
that  the  system  of  bones,  muscles,  and  nerves  of  this 
extremity  is  suited  to  every  fomi  and  condition  of  ver- 
tebrated  animals  ; and  we  must  confess  that  it  is  in 
the  human  hand  that  we  have  the  consummation  of 
all  perfection  as  an  instrument.  This,  we  perceive, 
consists  in  its  power,  which  is  a combination  of 
strength  with  variety  and  extent  of  motion  ; we  see 
it  in  the  forms,  relations,  and  sensibility  of  the  fingers 
and  thumb ; in  the  provisions  for  holding,  pulling,  spin- 
ning, weaving,  and  constructing  ; properties  which 
may  be  found  in  other  animals,  but  which  are  com- 
bined to  form  this  more  perfect  instrument. 

In  these  provisions  the  instrument  corresponds  with 
the  superior  mental  capacities,  the  hand  being  capa- 
ble of  executing  whatever  man’s  ingenuity  suggests. 
Nevertheless,  the  possession  of  the  ready  instru- 
ment is  not  the  cause  of  the  superiority  of  man,  nor 
is  its  aptness  the  measure  of  his  attainments.  So 
that  we  rather  say  with  Galen — that  man  had  hands 
given  to  him  because  he  Avas  the  wisest  creature, 
than  ascribe  his  superiority  and  knowledge  to  the 
use  of  his  hands.* 


* Ita  quidem  sapientissimum  an'iraalium  est  homo  ; ita  autem  et 
manus  sunt  organa  sapienti  animali  convenientia.  Non  enim  quia 

14 


158 


THE  HAND  NOT  THE 


This  question  has  arisen  from  observing  the  perfect 
correspondence  between  the  propensities  of  animals 
and  their  forms  and  outward  organization.  When 
we  see  a heron  standing  by  the  water  side,  still  as  a 
grey  stone,  and  hardly  distinguishable  from  it,  we 
may  ascribe  this  habit  to  the  acquired  use  of  its  feet, 
constructed  for  wading,  and  to  its  long  bill  and  flex- 
ible neck  ; for  the  neck  and  bill  are  as  much  suited 
to  its  wants  as  the  lister  is  to  the  fisherman.  But 
there  is  nothing  in  the  configuration  of  the  black 
bear  particularly  adapted  to  catch  fish  ; yet  he  will 
sit  on  his  hinder  extremities  by  the  side  of  a stream, 
in  the  morning  or  evening,  like  a practised  fisher ; 
there  he  will  watch,  so  motionless  as  to  deceive  the 
eye  of  tlie  Indian,  who  mistakes  him  for  the  burnt 
trunk  of  a tree  ; and  ^\^th  his  fore  paw  he  vrill  seize 
a fish  with  incredible  celerity.  The  exterior  organ 
is  not,  in  this  instance,  the  cause  of  the  habit  or  of 
the  propensity  ; and  if  we  see  the  animal  in  posses- 
sion of  the  instinct  without  the  appropriate  organ, 
we  can  the  more  readily  believe  that,  in  other  exam- 
ples, the  habit  exists  with  the  instrument,  although 
not  through  it. 

The  canine  teeth  are  not  given  without  the  carni- 
vorous appetite,  nor  is  the  necessity  of  living  by  car- 
nage joined  to  a timid  disposition  ; but  boldness  and 
fierceness,  as  ^vell  as  cunning,  belong  to  the  animal 
with  retractile  claws  and  sharp  teeth,  and  which  pre\' 
on  living  animals.*  On  the  other  hand,  the  timid 
vegetable  feeder  has  not  his  propensities  produced  by 


manus  habuit  propterea  est  sapientissimuni,  ut  Anaxagoras  dicebat : 
sed  quia  sapientissimuni  erat,  propier  hoc  manus  habuit,  utreclissime 
censuit  Aristoteles.  Non  enim  manus  ipsae  homines  artes  docuenmt, 
sed  ratio.  Manus  auteni  ipsae  sunt  artium  organa:  sicut  lyraq  mu- 
sici,  et  forceps,  fabri. 

* In  some  of  the  quadrumana,  the  canine  teeth  are  as  long  and 
sharp  as  those  of  the  tiger — but  they  are  in  them  only  instruments 
of  defence,  and  have  no  relation  to  the  appetite,  or  mode  of  diges- 
tion, or  intern.al  organization. 


SOURCE  OF  INGENUITY. 


159 


the  erect  ears  and  prominent  eyes  ; though  his  dis- 
position corresponds  with  them  in  his  suspicious- 
ness and  timidity.  The  boldness  of  the  bison  or 
buffalo  may  be  as  great  as  that  of  the  lion  ; but  the 
impulse  is  different — there  is  a direction  given  to  him 
by  instinct  to  strike  with  his  horns  ; and  he  will  so  push 
whether  he  has  horns  or  not.  “ The  young  calf  will 
“ butt  against  you  before  he  has  horns,”  says  Galen  : 
and  the  Scotch  song  has  it  “ the  putting  cow  is 
ay  a doddy,”  that  is,  the  humble  cow  (inermis),  al- 
though wanting  horns,  is  always  the  most  mischiev- 
ous. When  that  noble  animal,  the  Brahmin  bull,  of 
the  Zoological  Gardens,  first  put  his  hoof  on  the  sod 
and  smelt  the  fresh  grass  after  his  voyage, — placid 
and  easily  managed  before,  he  became  excited,  plung- 
ed, and  struck  his  horns  into  the  earth,  and  ploughed 
up  the  ground  on  alternate  sides,  with  a very  remark- 
able precision.  This  was  his  dangerous  play  ; just  as 
the  dog,  in  his  gambols,  worries  and  fights  : or  the  cat, 
though  pleased,  puts  out  its  claws.  It  would,  indeed, 
be  strange,  where  all  else  is  perfect,  if  the  instinctive 
character  or  disposition  of  the  animal  were  at  vari- 
ance with  its  arms  or  instruments. 

But  the  idea  may  still  be  entertained  that  the  acci- 
dental use  of  the  organ  may  conduce  to  its  moie 
frequent  exercise  and  to  the  production  of  a corres- 
ponding disposition.  Such  an  hypothesis  would  not 
explain  the  facts.  The  late  Sir  Joseph  Banks,  in  his 
evening  conversations,  told  us  that  he  had  seen,  what 
many  perhaps  have  seen,  a chidren  catch  at  a fly 
whilst  the  shell  stuck  to  its  tail.  Sir  Humphry  Davy 
relates  that  a friend  of  his  having  discovered  under  the 
burning  sand  of  Ceylon,  the  eggs  of  the  alligator,  he 
had  the  curiosity  to  break  one  of  them ; when  a 
young  alligator  came  forth,  perfect  in  its  motions  and 
in  its  passions  ; for  although  hatched  under  the  in- 
fluence of  the  sunbeams  in  the  burning  sand,  it  made 
towards  the  water,  its  proper  element  ; when  hinder- 
ed, it  assumed  a threatening  aspect  and  bit  the  stick 


160 


INSTINCT  OF  THE  TOUNG  ANIMAL. 


presented  to  it.  As  propensities  to  certain  motions  are 
implanted  in  animals,  to  which  their  external  organs 
are  subservient,  so  are  passions  given  as  the  means 
of  defence  or  of  obtaining  food.  But  this  has  been 
well  said  seventeen  hundred  years  ago.  “ Take,” 
says  Galen,  “ three  eggs,  one  of  an  eagle,  another 
“ of  a goose,  and  a third  of  a \dper ; and  place  them 
“ favourably  for  hatching.  When  the  shells  a^e 
“ broken,  the  eaglet  and  the  gosling  will  attempt  to 
“ fly ; while  the  young  of  the  viper  will  coil  and  twist 
“ along  the  ground.  If  the  experiment  be  protracted 
“ to  a later  period,  the  eagle  wll  soar  to  the  highest 
“ regions  of  the  air,  the  goose  betake  itself  to  the 
“ marshy  pool,  and  the  wper  will  bury  itself  in  the 
“ ground.” 

When  we  direct  the  enquiry  to  the  comparison  of 
man’s  faculties  with  his  outward  organization,  the 
subject  has  increased  interest.  With  the  possession 
of  an  instrument  like  the  hand  there  must  be  a 
great  part  of  the  organization,  which  strictly  belongs 
to  it,  concealed.  The  hand  is  not  a thing  appended, 
or  put  on,  like  an  additional  movement  in  a watch  ; 
but  a thousand  intricate  relations  must  be  established 
tliroughoui  the  body  in  connection  with  it — such  as 
nerves  of  motion  and  nerves  of  sensation  : and  there 
must  be  an  original  part  of  the  composition  of  the 
brain,  which  shall  have  relation  to  these  new  parts, 
before  they  can  be  put  in  activity.  But  even  with 
all  this  superadded  organization  the  hand  would  lie 
inactive,  unless  there  were  created  a propensity  to 
put  it  into  operation. 

I have  been  asked  by  men  of  the  first  education 
and  talents  whether  any  thing  really  deficient  had 
been  discovered  in  the  organs  of  the  orang-outang  to 
prevent  him  from  speaking  ! The  reader  v.'ill  give 
me  leave  to  place  this  matter  coiTectly  before  him. 
In  speaking,  there  is  first  required  a certain  force  of 
expired  air,  or  an  action  of  the  muscles  of  respiration  ; 
in  the  second  place,  the  vocal  chords  in  the  top  of 


THE  SUBJECT  ILLUSTRATED. 


161 


the  wind-pipe  must  be  drawn  into  accordance  by 
their  muscles,  else  no  vibration  will  take  place,  and 
no  sound  issue ; thirdly,  the  open  passages  of  the 
throat  must  be  expanded,  contracted,  or  extended  by 
their  numerous  muscles,  in  correspondence  with  the 
condition  of  the  vocal  chords  or  glottis  ; and  these 
must  all  sympathise  before  even  a simple  sound  is 
produced.  But  to  articulate  that  sound,  so  that  it 
may  become  a part  of  a conventional  language, 
there  must  be  added  an  action  of  the  pharynx,  of  the 
palate,  of  the  tongue  and  lips.  The  exquisite  organi- 
zation for  all  this  is  not  visible  in  the  organs  of  tire 
voice,  as  they  are  called : it  is  to  be  found  in  the 
nerves  which  combine  all  these  various  parts  in  one 
simultaneous  act.  The  meshes  of  the  spider’s  web, 
or  the  cordage  of  a man-of-war,  are  few  and  simple 
compared  with  the  concealed  filaments  of  nerves 
which  move  these  parts  ; and  if  but  one  be  wanting, 
or  its  tone  or  action  disturbed  in  the  slightest  degree, 
every  body  knows  how  a man  will  stand  with  liis 
mouth  open,  twisting  his  tongue  and  lips  in  vain 
attempts  to  utter  a word. 

It  will  now  appear  that  there  must  be  distinct  lines 
of  association  suited  to  the  organs  of  voice — difierent 
to  combine  them  in  the  bark  of  a dog,  in  the  neigh- 
ing of  a horse,  or  in  the  shrill  whistle  of  the  ape. 
That  there  are  wide  distinctions  in  the  structure  of 
the  different  classes  of  animals  is  most  certain  ; but 
independently  of  those  which  are  apparent,  there  are 
secret  and  minuie  varieties  in  the  associating  cords. 
The  ape,  therefore,  does  not  articulate — First,  because 
the  organs  are  not  perfect  to  this  end.  Secondly, 
because  the  nerves  do  not  associate  these  organs  in 
that  variety  of  action  v/hich  is  necessary  to  speech. 
And,  lastly,  were  all  the  exterior  apparatus  perfect, 
there  is  no  impulse  to  that  act  of  speaking. 

Now  I hope  it  appears,  from  thise  numeration  of 
parts,  that  the  main  difference  lies  in  tlie  internal 
faculty  or  propensity.  As  soon  as  a child  can  distin- 
14* 


162 


THE  INGENUITY  OF  THE  HAND 


guish  and  admire,  then  are  its  features  in  action  ; its 
voice  begins  to  be  modified  into  a variety  of  sounds  ; 
these  are  taken  up  and  repeated  by  the  nurse,  and 
already  a sort  of  convention  is  established  between 
them.  We  cannot,  therefore,  doubt  that  a propensity 
is  created  in  correspondence  with  the  outward  organs, 
and  without  which  they  would  be  useless  appendages. 
The  aptness  of  the  instrument  or  external  organ  will 
undoubtedly  improve  the  faculty,  just  as  we  find  that 
giving  freedom  to  the  expression  of  passion  adds  force 
to  the  emotion  in  the  mind. 

One  cannot  but  reflect  here  on  that  grand  revolu- 
tion which  took  place  when  language,  till  then  limit- 
ed to  its  proper  organ,  had  its  representation  in  the 
work  of  the  hand.  IVow  that  a man  of  mean  estate 
can  have  a library  of  more  intrinsic  value  than  that 
of  Cicero,  when  the  sentiments  of  past  ages  are  as 
familiar  as  those  of  the  present,  and  the  knowledge  of 
diflerent  empires  is  transmitted  and  common  to  all, 
we  cannot  expect  to  have  our  sages  followed,  as  of 
old,  by  their  five  thousand  scholars.  Nations  will 
not  now  record  their  acts  by  building  pyramids,  nor 
consecrate  temples  and  raise  statues,  once  the  onl}’ 
means  of  perpetuating  great  deeds  or  extraordinary 
virtues.  It  is  in  vain  that  our  artists  complain  that 
patronage  is  Avithheld  : for  the  ingenuity  of  the  hand 
has  at  length  subdued  the  arts  of  design — printing 
has  made  all  other  records  barbarous,  and  gi'eat  men 
build  for  themselves  a “ livelong  monument.” 

Buffbn  has  attempted  to  convey  to  us  the  mode  in 
which  knowledge  may  have  been  accjuired  by  watch- 
ing (in  fancy)  the  newly  awakened  senses  in  the  first 
created  Man  ; but,  for  that  which  is  consistent  and 
splendid  in  our  great  poet — who  makes  him  raise  his 
wondering  eyes  to  Heaven  and  sprmg  up  bt’  quick 
instinctive  motion  as  “ thitherward  endeavouring,”  he 
substitutes  a bad  combination  of  philosophy  with 
eloquence. 


HAS  MADE  A REVOLUTION  IN  THE  ARTS.  163 

“To  place  the  subject  more  distinctly  before  ns,” 
says  Bulfon,  “ the  first  created  man  shall  speak  for 
“ himself and  the  sentence  which  he  is  made  to  utter 
is  to  the  effect, — “ that  he  remembers  the  moment 
“ of  his  creation — that  time,  so  full  of  joy  and  trouble, 
“ when  he  first  looked  round  on  the  verdant  lawns  and 
“ crystal  fountains,  and  saw  the  vault  of  Heaven  over 
“ his  head  — and  he  proceeds  to  declare, — “ that  he 
“ knew  not  what  he  was  or  whence  he  came,  and  be- 
“lieved  that  all  he  saw  was  part  of  himself.”  He  is 
thus  represented  to  be  conscious  of  objects,  which 
even  to  see  implies  experience,  and  to  enjoy,  sup- 
poses a thousand  disagreeable  associations  already 
formed  ; — but  from  this  blissful  state  he  is  awakened 
by  striking  his  head  against  a palm  tree,  which  he 
had  not  yet  learned  could  hurt  him  ! 

Men  are  diffident  of  their  first  notions,  and  con- 
ceive that  philosophy  must  lead  to  something  very 
different  from  what  they  have  been  -early  taught: 
hence  the  absurdity  of  this  combination  of  philosophy 
and  poetry.  Later  writers  have  argued  that  we  have 
no  right  to  suppose  that  there  has  been,  at  any  time, 
an  interruption  to  the  course  of  nature.  What  the}^ 
term  the  uniformity  of  nature,  is  the  prevalence  of  the 
same  laws  which  are  now  in  operation.  If,  say  they, 
it  happened  that  on  the  arrival  of  a colony  in  a new 
country,  fruits  Avere  produced  spontaneously  around 
them,  and  flowers  sprung  up  under  their  feet,  then, 
we  might  suppose  that  our  first  parents  were  placed 
in  a scene  of  beauty  and  profusion — suited  to  their 
helpless  condition — and  unlike  Avhat  we  see  now  in 
the  course  of  nature. 

It  is  not  very  Avise  to  entertain  the  subject  at  all, 
but  if  it  is  to  be  argued,  this  is  starting  altogether 
Avide  of  the  question.  We  do  not  desire  to  knoAV  hoAV  a 
tribe  migrating  westAvard  could  find  sustenance,  but 
in  AA’hat  state  man  could  be  created  to  live  Avithout 
a deviation  from  Avhat  is  called  the  coui’se  of  nature. 

If  man  had  been  formed  helpless  as  an  infant,  he 


164 


CHANGES  IN  THE  GLOBE 


must  have  perished  ; and  if  mature  in  body,  he  must 
have  been  created  with  faculties  suited  to  his  condi- 
tion. A human  being,  pure  from  the  Maker’s  hands, 
with  desires  and  passions  implanted  in  him,  adapted 
to  his  state,  and  with  a suitable  theatre  of  existence, 
implies  something  very  near  what  Ave  have  been  ear- 
ly taught  to  believe. 

In  every  change  which  the  globe  has  undergone, 
we  see  an  established  relation  between  the  animal 
created,  and  the  elements  around  it.  It  is  idle  to  sup- 
pose this  a matter  of  chance.  Either  the  structure 
and  functions  of  the  animal  must  haA’e  been  formed 
to  correspond  with  the  condition  of  the  elements,  or 
the  elements  must  have  been  controlled  to  minister 
to  the  necessities  of  the  animal ; and  if  the  most  care- 
ful investigation  lead  us  to  this  conclusion,  in  con- 
templating all  the  inferior  gradations  of  animal  exis- 
tence, what  is  it  that  makes  us  so  unwilling  to  ad- 
mit such  an  influence  in  the  last  grand  work  of 
creation  1 

We  cannot  resist  those  proofs  of  a beginning,  or  of 
design  prevailing  everywhere,  or  of  a First  Cause. 
When  Ave  are  bold  enough  to  extend  our  inquiries  in- 
to the  great  reA'olutions  Avhich  lia\"e  taken  place, 
Avhether  in  the  condition  of  the  earth  or  in  the  struc- 
ture of  the  animals  Avhich  have  inhabited  it,  our  no- 
tions of  the  unifonnity  of  the  course  of  nature  must 
suflfer  some  modification.  Changes  must,  at  certain 
epochs,  have  been  Avrought,  and  neAV  beings  brought 
into  existence  dilferent  from  the  order  of  things  pre\  i- 
ously  existing,  or  noAV  existing:  and  such  interference 
is  not  contraiy  to  the  great  scheme  of  creation.  It  is 
not  contrary  to  that  scheme,  but  only  to  our  present 
state.  For  the  most  Avise  and  benevolent  purposes,  a 
conviction  is  implanted  in  our  nature  that  Ave  should 
rely  on  the  course  of  eA-ents,  as  permanent  and  neces- 
sary. We  belong  to  a certain  epoch  ; and  it  is  Avhen 
our  ambitious  thoughts  carry  us  beyond  our  natural 
condition,  that  Ave  feel  hoAv  much  our  faculties  are 


AND  SUCCESSIVE  EPOCHS. 


165 


constrained,  and  our  conceptions,  as  well  as  our  lan- 
guage, imperfect.  We  must  either  abandon  these 
speculations  altogether,  or  cease  to  argue  purely  from 
our  present  situation. 

It  has  been  made  manifest  that  man  and  the  animals 
inhabiting  the  earth  have  been  created  with  reference 
to  the  magnitude  of  the  globe  itself ; — that  their  living 
endowments  bear  a relation  to  their  state  of  exis- 
tence and  to  the  elements  around  them.  We  have 
learnt  that  the  system  of  animal  bodies  is  simple  and 
universal,  notwithstanding  the  amazing  diversit}’  of 
forms  that  meet  the  eye — and  that  this  system  not 
only  embraces  all  living  creatures,  but  that  it  has  been 
in  operation  at  periods  of  gi-eat  antiquity,  before  the 
last  revolution  of  the  earth’s  surface  had  been  accom- 
plished. 

The  most  obvious  appearances  and  the  labours  of 
the  geologist  give  us  reason  to  believe  that  the  earth 
has  not  always  been  in  the  state  in  which  it  is  now 
presented  to  us.  Every  substance  which  we  see  is 
compound ; we  nowhere  obtain  the  elements  of  things : 
the  most  solid  materials  of  the  globe  are  formed  of 
decompounded  and  reunited  parts.  Changes  have 
been  wrought  on  the  general  surface,  and  the  proofs 
of  these  changes  are  as  distinct  as  the  furrows  on  a 
field  are  indicative  that  the  plough  has  passed  over  it. 
The  deeper  parts  of  the  crust  of  the  earth  and  the 
animal  remains  imbedded,  also  give  proofs  of  revolu- 
tions : and  that  in  the  coinse  of  these  revolutions  there 
have  been  long  periods  or  epochs.  In  short,  progres- 
sive changes,  from  the  lowest  to  the  highest  state  of 
existence,  of  organization  and  of  enjoyment,  point  to 
the  great  truth  that  there  was  a beginning. 

When  the  geologist  sees  a succession  of  stratified 
rocks — the  lowest  simple,  or  perhaps  chemical ; the 
strata  above  these,  compound ; and  successively  others 
more  conglomerated,  or  more  distinctly  composed  of 
the  fragments  of  the  former — it  is  not  easy  to  contra^ 


166  COMPARISON  OF  SOME  PARTS  OF  THE 

diet  the  hypothesis  of  an  eternal  succession  of  causes. 
But  there  is  nothing  like  this  in  the  animal  bod}',  the 
material  is  the  same  in  all,  the  general  design  too  is 
the  same ; but  each  family,  as  it  is  created,  is  sub- 
mitted to  such  new  and  fundamental  arrangements 
in  its  construction  as  implies  the  presence  of  the  hand 
of  the  Creator. 

There  is  nothing  in  the  inspection  of  the  species  of 
animals,  which  countenances  the  notion  of  a retiun 
of  the  world  to  any  former  condition.  When  we  ac- 
knowledge that  animals  have  been  created  in  suc- 
cession and  with  an  increasing  complexity  of  parts, 
we  are  not  to  be  understood  as  admitting  that  there 
is  here  proof  of  a growing  maturity  of  power,  or  an 
increasing  effort  in  the  Creator ; and  for  this  veiy 
plain  reason,  which  we  have  stated,  that  the  bestow- 
ing of  life  or  the  union  of  the  ntal  principle  with  the 
material  body,  is  the  manifestation  of  a power  supe- 
rior to  that  displayed  in  the  formation  of  an  organ  or  the 
combination  of  many  organs,  or  construction  of  the 
most  complex  mechanism.  It  is  not,  therefore,  a 
greater  power  that  we  see  in  operation,  but  a power 
manifesting  itself  in  the  perfect  and  successive  adap- 
tation of  one  thing  to  another — of  vitality  and  organi- 
zation to  inorganic  matter. 

In  contemplating  the  chain  of  animal  creation,  we 
observe  that  even  now,  there  are  parts  of  the  earth’s 
surface  which  are  marshy,  and  insalubrious,  and  that 
these  are  the  places  inhabited  by  amphibious  and 
web-footed  animals, — such  as  are  suited  to  the  oozy 
margins  of  swamps,  lakes  or  estuaries.  It  is  most  in- 
teresting to  find  that  when  the  remains  of  animals  of 
similar  construction,  are  found  in  the  sohd  rocks,  the 
geologist  discovers  by  other  signs  that  at  the  period 
of  the  formation  of  these  rocks,  the  siuface  was  flat, 
and  that  it  produced  such  plants  as  imply  a similar 
state  of  the  earth  to  these  swampy  and  unhealthy 
regions. 

We  mark  changes  in  the  earth’s  surface,  and  ob- 


EARTH  WITH  A FORMER  CONDITION. 


167 


serve,  at  the  same  time,  corresponding  changes  in 
the  animal  creation.  We  remark  varieties  in  the 
outward  form,  size  and  general  condition  of  animals, 
and  corresponding  varieties  in  the  internal  organiza- 
tion,— until  we  find  men  created  of  undoubted  pre- 
eminence over  all,  and  placed  suitably  in  a bounte- 
ous condition  of  the  earth. 

Most  certainly  the  original  crust  of  the  earth  has 
been  fractured  and  burst  up,  so  as  to  expose  its  con- 
tents ; that  they  might  be  resolved  and  washed  away, 
by  the  vicissitudes  of  heat,  cold,  and  rain.  Moun- 
tains and  valle}"s  have  been  formed  ; the  changes  of 
temperature  in  the  atmosphere  have  ensured  continu- 
al motion  and  healthful  circulation  : tlie  plains  have 
been  made  salubrious,  and  the  damps  which  hung  on 
the  low  grounds  have  gathered  on  the  mountains  in 
clouds,  so  that  refreshing  showers  have  brought  down 
the  soil  to  fertilize  the  plain  ; thus  at  once  have  been 
supplied  tlie  means  for  man’s  existence,  with  objects 
suited  to  excite  his  ingenuit}’’,  and  to  reward  it,  and 
fitted  to  develope  all  the  various  properties  both  of  his 
body  and  of  his  mind. 

There  is  extreme  gi’andeur  in  the  thought  of  an 
anticipating  or  prospective  intelligence  : in  reflecting 
that  what  was  finally  accomplished  in  man,  was 
begun  in  times  incalculably  remote,  and  antecedent 
to  the  great  revolutions  which  the  earth’s  surface  has 
undergone.  Nor  are  these  conclusions  too  vast  to  be 
drawn  from  the  examination  of  a part  so  small  as  the 
Irenes  of  the  hand ; since  we  have  shown  that  the 
same  system  of  parts  which  constitutes  the  perfection 
of  that  instrument  adapted  to  our  condition,  had  its 
type  in  the  members  of  those  vast  animals  which  in- 
habited the  bays,  and  inland  lakes  of  a former  world. 
If  we  seek  to  discover  the  relations  of  things,  how  sub- 
lime is  the  relation  established  between  that  state  of 
the  earth’s  surface,  which  has  resulted  from  a long  suc- 
cession of  revolutions,  and  the  final  condition  of  its  in- 
habitants as  created  in  accordance  with  the  change. 


168 


CONCLUSION. 


Nothing  is  more  smprismg  to  our  measure  of  time, 
than  the  slowness  with  which  the  designs  of  Provi- 
dence have  been  fulfilled.  But  as  far  as  we  can 
penetrate  by  the  light  of  natural  knowledge,  the  con- 
dition of  the  earth,  and  with  it  of  man’s  destinies, 
have  hitherto  been  accomplished  in  great  epochs. 

We  have  been  engaged  in  comparing  the  structure, 
organs,  and  capacity  of  man  and  of  animals — we 
have  traced  a relation — but  we  have  also  observed  a 
broad  line  of  separation  : man  alone  capable  of  rea- 
son, affection,  gratitude,  and  religion  : sensible  to 
the  progress  of  time,  conscious  of  the  decay  of  his 
strength  and  faculties,  of  the  loss  of  friends,  and  the 
approach  of  death. 

One  who  was  the  idol  of  his  day  has  recorded 
his  feelings  in  nearly  these  words, — “ We  are  as  well 
as  those  can  be  w'ho  have  nothing  further  to  hope  or 
fear  in  this  world.  W e go  in  and  out,  but  without 
the  sentiments  that  can  create  attaclnneut  to  any 
spot.  We  are  in  a state  of  quiet,  but  it  is  the  tran- 
quillity of  the  grave,  in  which  all  that  could  make 
life  interesting  to  us  is  laid.”  If  in  such  a state  there 
were  no  refuge  for  the  mind,  then  were  there  some- 
thing wanting  in  the  scheme  of  nature  : an  imper- 

fection in  man’s  condition  at  variance  with  the 
benevolence  which  is  manifested  in  all  other  parts  of 
animated  nature. 


ADDITIONAL  ILLUSTRATIONS. 


15 


ADDITIONAL  ILLUSTRATIONS. 


THE  MECHANICAL  PROPERTIES  OP  THE  SOLID  STRUC- 
TURE OF  THE  ANIMAL  BODY  CONSIDERED. 

I YIELD  to  the  suggestion  of  friends  in  further  pur- 
suing the  subject  of  the  solid  textures  of  the  animal 
frame,  with  the  proofs  of  design  which  are  exhibited 
in  its  mechanical  provisions. 

It  has  been  shown  in  the  first  chapter  that  solidity 
and  gravity  are  qualities  necessary  to  everjr  inhabitant 
of  the  earth  : the  first  to  protect  it ; the  second,  that 
the  animal  may  stand,  and  possess  that  resistance, 
which  shall  make  the  muscles  available  for  action. 

The  first  material  to  be  taken  notice  of,  which  lie- 
stows  this  necessary  firmness  on  the  animal  textures, 
is  the  cellular  substance.  This  consists  of  delicate  mem- 
branes, which  form  cells ; these  cells  communicate 
with  each  other,  and  the  tissue  thus  composed  enters 
every  where  into  the  structure  of  the  animal  frame. 
It  constitutes  the  principal  part  of  the  medusa,  which 
floats  like  a bubble  on  the  water  ; and  it  is  found  in 
every  texture  of  the  human  body.  It  forms  the  most 
delicate  coats  of  the  eye,  and  gives  toughness  and 
fianness  to  the  skin.  It  is  twisted  into  ligaments, 
and  knits  the  strongest  bones  : it  is  the  medium  be- 
tween bone,  muscle,  and  blood-vessel ; it  produces  a 
certain  firmness  and  union  of  the  various  component 
parts  of  the  body  while  it  admits  of  their  easy  motion. 
Without  it,  we  should  be  rigid,  notwithstanding  the 
proper  organs  for  motion ; and  the  cavities  could  not 
be  distended  or  contracted,  nor  could  the  vessels 
pulsate. 

But  this  cellular  texture  is  not  sufficient  on  all  oc- 
casions, either  for  giving  strength  or  protection  ; ncsC 


172 


ADDITIONAL  ILLUSTRATIONS 


does  it  serve  to  sustain  the  weight,  unless  the  anhnal 
live  suspended  in  water,  or  creep  upon  the  ground. 
We  see,  therefore,  the  necessity  for  some  harder  and 
more  resisting  material  being  added,  if  the  weight  is 
to  rest  on  points  or  extremities  ; or  if  the  muscular 
activity  is  to  be  concentrated. 

Nature  has  other  means  of  supplying  the  fulcnun 
and  lever,  besides  the  bones,  or  true  skeleton,  which 
we  have  been  examining  in  the  fii’st  part  of  this  vo- 
lume ; and  perhaps  we  shall  find  that  there  may  be  a 
system  of  solid  parts  superior  to  what  we  have  been 
studying  in  the  vertebrata. 

The  larvae  of  proper  insects  and  the  annelides  have 
no  exterior  members  for  walking  or  flying : but  to 
enable  them  to  creep,  they  must  have  points  of  re- 
sistance, or  their  muscles  would  be  useless.  Their 
skins  suffice  ; they  are  hardened  by  a deposit  \vithin 
them  for  this  purpose  ; but  if  this  skin  were  not  fur- 
ther provided,  it  would  be  rigid  and  unyielding,  and 
be  no  substitute  for  bone.  These  hardened  integu- 
ments are,  therefore,  divided  into  rings  ; to  these  the 
muscles  are  attached  ; and  as  the  cellular  membrane 
between  the  rings  is  pliant,  these  annelides  can  creep 
and  turn  in  every  direction. 

Without  further  argument,  we  perceive  how  the 
skin,  by  having  a hard  matter  deposited  in  it,  is  adap- 
ted to  all  the  purposes  of  the  skeleton.  It  is  worthy 
of  notice  that  some  animals,  still  lower  in  the  scale, — 
the  tubipores,  sertularia,  cellularia,  &c.,  exhibit  some- 
thing like  a skeleton.  Tliey  are  contained  within  a 
strong  case  from  which  they  can  extend  themselves  : 
whilst  the  corals  and  madrepores,  on  the  other  hand, 
have  a central  axis  of  hard  material,  the  soft  animal 
substance  being,  in  amanner,  seated  uponit.  But  these 
substitutes  for  the  skeleton  are,  like  shell,  foreign  to  the 
living  animal ; although  in  office  they  may  resemble 
bone  in  sustainingthe  softer  substance  and  giving  form. 

In  the  proper  insect  I should  say  that  there  is  a 
nearer  approach  to  a skeleton,  did  it  not  appear  that 


OF  THE  MECHANICAL  PROPERTIES.  ITS 

the  apparatus  is  more  perfect  than  in  some  of  the  ani- 
mals which  have  a true  skeleton.  The  resisting  ma- 
terial is  here  deposited  externally,  and  is  converted  to 
every  purpose  which  we  have  seen  attained  by  means 
of  the  skeleton.  Distinct  members  are  formed,  with 
the  power  of  walking,  leaping,  flying,  holding,  spin- 
ning, and  weaving.  The  hardened  integuments, 
thus  articulated  and  performing  the  office  of  bones, 
have,  like  them,  spines  and  processes  : with  this  dif- 
ference, that  their  aspect  is  towards  the  centre,  instead 
of  projecting  exteriorly.  Were  Ave  to  compare  the 
system  of  “ resisting  parts”  in  man  and  in  the  insect, 
Ave  should  be  forced  to  acknoAvledge  the  mechanical 
provisions  to  be  superior  in  the  lower  animal  ! The 
first  advantage  of  the  skeleton  (as  we  may  be  permit- 
ted to  call  the  system  of  hard  parts  in  the  insect)  be- 
ing external  and  lifeless,  is,  that  it  is  capable  of  hav- 
ing greater  hardness  and  strength  bestoAA'ed  upon  it, 
according  to  the  necessities  of  the  animal,  than  can 
be  bestoAved  upon  bone  : true  bone  being  internal  and 
growing  with  the  animal,  is  penetrated  with  blood 
vessels  ; and  therefore  must  be  porous  and  soft.  The 
next  advantage  is  mechanical.  The  hard  material  is 
strong  to  resist  fracture,  and  to  bear  the  action  of  mus- 
cles, in  proportion  to  its  distance  from  the  centre  : for 
the  muscles  in  the  insect,  instead  of  surrounding  the 
bones,  as  in  the  higher  animals,  are  contained  within 
the  shell,  and  the  shell  is,  consequently,  so  much  the 
further  throAAUi  off  from  the  axis. 

When  considering  the  larger  A’ertebral  animals,  we 
had  reason  to  say  that  there  is  a correspondence  be- 
tween the  resistance  of  the  bones  and  the  poAver  of 
the  muscles,  and  Ave  may  indulge  the  same  reflection 
here.  As  the  integument  coA’ering  the  insect  is  much 
harder  than  bone,  so  are  the  muscles  stronger,  com- 
pared AA’ith  the  muscles  of  the  A’ertebrata.  From  the 
time  of  Socrates,  comparisons  have  been  made  between 
the  strength  of  the  horse  and  of  the  insect  ; to  the 
obvious  superiority  of  the  latter. 

15* 


174 


ILLUSTRATIONS  OF  THE 


As  goodly  a volume  has  been  written  on  the  mus- 
cles of  a caterpillar  as  has  ever  been  dedicated  to  the 
human  myology.  A very  minute  anatomical  de- 
scription has  been  made  of  the  caterpillar  which  feeds 
upon  the  willow  ; and  here  we  see  that  the  annular 
construction  of  the  hard  integument  determines  the 
plan  of  the  whole  anatomy  : the  arrangement  of  the 
muscles,  and  the  distribution  of  the  ner\*es.  Each 
ring  has  its  three  sets  of  muscles ; direct,  oblique, 
traversing  and  interweavmg,  but  yet  distinct  and 
symmetrical ; and  all  as  capable  of  being  minutely 
described  as  those  of  the  human  body  have  been  by 
Albinus.*  Corresponding  with  these  muscles,  the 
system  of  nerves  is  delicately  laid  down.  In  short, 
we  allow  ourselves  to  be  misled  in  supposing  that  ani- 
mals, either  of  minute  size  or  low  in  the  scale  of 
arrangement,  exhibit  any  neglect  or  imperfection. 
Even  if  they  were  more  simple  in  structure,  the  admi- 
ration should  be  the  greater  : since  they  have  all  the 
functions  in  full  operation  which  are  necessary  to  life. 

We  may  perceive  that  a certain  substance  calcu- 
lated to  sustain  the  more  strictly  livuig  part,  and  to 
give  strength,  may  be  traced  through  all  living  bodies. 
In  the  vegetable  it  is  the  woody  fibre ; and  there, 
sometimes,  as  if  to  mark  the  analog)',  we  may  find 
silicious  earth  deposited  instead  of  the  phosphate  and 
carbonate  of  lime  of  the  anunal  structure.  In  the 
lower  animals  we  find  membranes  capable  of  secre- 
ting a solid  material,  and  although  in  some  instances 
the  substance  is  like  leather  or  cartilage,  it  is  in  gene- 
ral earthy,  and  for  the  most  part,  carbonate  of  lime. 
But  when  elasticity  is  necessary,  as  well  as  general 
resistance,  cartilage  is  employed,  which  is  a highly 
comprehensible  and  elastic  substance.  Thus,  in  fish- 
es, there  is  a large  proportion  of  cartilage  in  their 
bones,  and  from  this  greater  quantity,  some  have 

* The  work  referred  to  is  by  Lyonnet,  who  reckons  four  thousand 
and  sixty  one  muscles  in  this  caterpillar.  He  was,  I think,  a law- 
yer, with  little  to  do. 


MECHANICAL  PROPERTIES  OF  BONE. 


175 


been  called  cartilaginous  in  distinction  to  tlie  osseous 
or  true  fishes.  The  cartilaginous  and  elastic  skele- 
ton is  brought  into  use  in  an  unexpected  manner : 
when  the  salmon  or  trout  leaps  from  the  water,  the 
muscles  bend  the  elastic  spine, — which  recoils  in  aid 
of  the  muscles  of  the  opposite  class  : and  thus  these 
two  forces  combine  to  give  a powerful  stroke  with  the 
tail  on  the  water. 


MECHANICAL  PROPERTIES  IN  BONE  OR  IN  THE  TRUE 
SKELETON. 

These  considerations  lead  us  the  more  readily  to 
understand  the  composition  of  bone  : which  is  a com- 
bination of  three  parts  having  different  properties, — 
membrane,  phosphate  of  lime,  and  cartilage.  By 
these  it  is  enabled  to  resist  stretching,  compression, 
and  tortion.  If  bone  had  a superabundance  of  the 
earthy  parts,  it  would  break  like  a piece  of  porcelain ; 
and  if  it  did  not  possess  toughness  and  some  degree 
of  elasticity,  it  would  not  enable  a man  to  pull  and 
push  and  twist. 

Looking  to  the  dense  bone,  we  should  hardly  sup- 
pose that  it  was  elastic  ; but  if  ivory  be  possessed  of 
elasticity,  it  cannot  be  denied  to  bone.  Now  if  a bil- 
liard ball  be  put  upon  a marble  slab  which  has  been 
painted,  a very  small  spot  will  mark  where  the  con- 
tact has  been  ; but  if  we  let  the  ball  drop  upon  the 
marble  from  a height,  we  shall  find  the  spot  much 
larger,  and  that  the  elasticity  of  the  ivory  has  per- 
mitted the  ball  to  yield  and  momentarily  to  assume 
an  oblate  spheroidal  form. 

When  a new  principle  is  admitted  into  a complex 
fabric,  the  utmost  ingenuity  can  hardly  anticipate  all 
the  results.  Elasticity  is  extensively  employed  in  the 
machinery  of  the  animal  body ; and  to  show  how  fine- 
ly it  must  be  apportioned,  we  shall  take  the  instance 
of  a bridge  built  with  iron  instead  of  stone,  and  hav- 


17G 


ILLUSTRATIONS  OF  THE  ‘ 


ing  a certain  swing  and  elasticity.  It  lately  happen- 
ed that  a bridge  of  this  kind  fell  in  veiy  curious  cir- 
cumstances,— by  the  inarching  of  a body  of  soldiers 
over  it.  Now  the  bridge  was  calculated  to  sustain  a 
greater  weight  than  this  body  of  men ; and  had  they 
walked  tumultuously  over  it,  it  would  have  with- 
stood the  pressure  ; but  the  soldiers  marching  to  time, 
accumulated  a motion,  aided  by  the  elasticit)'  of  the 
material,  which  broke  it  down.  This  leads  us  to 
form  a conception  of  the  necessity  of  the  fine  adjust- 
ment of  the  material  in  the  animal  fabric  ; not  mere- 
ly to  enable  it  to  sustain  the  incumbent  weight,  or 
transverse  or  oblique  impulses,  but  to  withstand  the 
frequent,  and  regularly  repeated  forces  to  which  it  may 
be  subject  in  the  various  actions  of  the  body.  It 
gives  interest  to  this  fact,  that  there  is  hardly  a bone 
but  what  has  a constitution  of  its  own,  adjusted  to  its 
place  and  use  : the  heel  bone,  the  shin  bone,  the  ver- 
tebrae, and  the  bones  of  the  head,  differ  in  mechani- 
cal construction.  But  the  consideration  of  these 
adaptations  in  the  constitution  of  the  bones  makes 
some  general  remarks  necessary. 

Perfect  security  against  accidents  in  the  animal 
body,  and  in  man  especially,  is  not  consistent  with  the 
scheme  of  nature.  Without  the  precautions  and  the 
continued  calls  to  exertion,  for  safety,  which  danger 
and  the  uncertainty  of  life  produce,  many  of  the  fa- 
culties of  the  mind  would  remain  unexercised  ; and 
whence  else  would  come  courage,  resolution,  and  all 
the  manly  virtues  ? Take  awaj'  the  influence  of  the 
uncertain  duration  of  life,  and  we  must  suppose  also 
a change  in  the  whole  moral  constitution  of  man. 
Whether  we  consider  the  bones  as  foimed  to  protect 
the  part,  as  in  the  skull ; or  to  be  levers  to  which  the 
muscles  are  attached,  as  in  the  limbs ; or  in  both 
capacities,  as  in  the  texture  of  the  chest  : while  they 
are  perfectly  adapted  to  their  function,  they  are  yet 
subject  to  derangements  from  accident.  The  me- 
chanical adaptations  which  we  have  to  observe  are 


MECHANICAL  PROPERTIES  OF  BONE. 


177 


perfectly  sufficient  to  their  ends,  and  afford  safety  in 
the  natural  exercises  of  the  body.  To  these  exer- 
cises there  is  an  intuitive  impulse,  ordered  with  a re- 
lation to  the  frame  of  the  body ; whilst,  on  the 
other  hand,  we  are  deterred  from  the  excessive  or 
dangerous  use  of  the  limbs  by  the  admonitions  of  pain. 
Without  such  considerations,  the  reader  would  fall 
into  the  mistake  that  weakness  and  liability  to  frac- 
ture implied  imperfection  in  the  frame  of  the  body: 
whereas  a deeper  contemplation  of  the  subject  will 
convince  him  of  the  incomparable  perfection  both  of 
the  plan  and  of  the  execution.  The  body  is  intended 
to  be  subject  to  derangement  and  accident,  and  to  be- 
come, in  the  course  of  life,  more  and  more  fragile, 
until  by  some  failure  in  the  frame-work  or  vital  ac- 
tions, life  terminates. 

The  bones  of  the  extremities  are  called  hollow 
cylinders.  Now,  after  we  have  convinced  ourselves 
of  the  necessity  of  this  formation,  we  find  these  bones, 
upon  a more  particular  examination,  extremely  varied 
in  their  shapes  : and  we  are,  at  last,  prone  to  believe 
that  there  is  much  of  chance  or  irregularity  in  their 
shapes  ; but  such  a conception  is  quite  inconsistent 
with  a correct  knowledge  of  the  skeleton.  As  this 
notion,  however,  is  very  commonly  entertained  and 
leads  to  further  mistakes,  we  shall  take  pains  to 
show, — first,  why  the  bones  are  hollow  ; and,  in  the 
second  place,  why  they  vary  in  their  shape,  so  as  to 
appear  to  the  superficial  observer  irregular. 

The  reasoning  that  applies  to  the  hollow  cylindrical 
bone  serves  equally  to  explain  many  other  natural 
forms,  as  that  of  a quill,  a reed,  or  a straw.  The  last 
example  reminds  us  of  the  unfortunate  man  who  was 
drawn  from  his  cell  before  the  Inquisition,  and  accu- 
sed of  having  denied  that  there  was  a God ; when  pick- 
ing up  a straw  that  had  stuck  to  his  garments,  he 
said,  “ If  there  were  nothing  else  in  nature  to  teach 
“ me  the  existence  of  a Deity,  this  straw  would  be 
“ sufficient.”  It  hardly  requires  demonstration  to 


178 


ILLUSTRATIONS  OF  THE 


prove  that,  with  a given  mass  of  material  to  make  a 
pillar  or  column,  the  hollow  cylinder  will  be  the 
form  of  strength.  The  experiments  of  Du  Hamel  on 
the  strength  of  beams  afford  us  the  best  illustration 
how  the  material  should  be  arranged  to  resist  transv 
verse  fracture.  When  a beam  rests  on  its  extremities, 
bearing  a weight  upon  its  centre,  it  admits  of  being 
divided  into  three  portions  ; for  these  three  parts  are 
in  a different  condition  with  regard  to  the  weight. 
The  lower  part  resists  fracture  by  its  toughness  ; the 
upper  part,  by  its  density  and  resistance  to  compres- 
sion : but  there  is  a portion  between  these  which  is 
not  acted  upon  at  all ; which  might  be  taken  away 
witliout  any  considerable  weakening  of  the  beam : 
and  which  might  be  added  to  the  upper  or  the  lower 
part  with  great  advantage.  It  can  readily  be  under- 
stood how  a tougher  substance  added  to  the  lower 
part  would  strengthen  the  beam : we  see  it  m the 
skin  which  is  laid  along  the  back  part  of  the  Indian’s 
boiv  ; or  in  the  leather  of  a caniage  spring : but  the 
following  is  a beautiful  experiment  to  demonstrate 
that  quality  in  the  timber  wliich  resists,  at  the  upper 
portion  of  the  beam.  If  a portion  amounting  to 
nearly  a third  part  of  the  beam  be  cut  away  and  a 
harder  piece  of  wood  be  nicely  let  into  the  space,  the 
strength  will  be  increased  ; because  the  hardness  of 
this  piece  of  wood  resists  compression.  This  experi- 
ment I like  the  better  because  it  explains  a very  in- 
teresting peculiarity  in  the  different  densities  of  the 
several  parts  or  sides  of  the  bones.  In  reading  anato- 
mical books,  we  are  led  to  the  supposition  that  the 
various  forms  of  the  bones  result  from  the  pressure  of 
the  muscles.  This  is  a mistake.  Were  we  to  con- 
sider this  the  true  explanation,  it  would  not  only  be 
admitting  an  imperfection,  but  Ave  should  expect  to 
find,  if  the  bones  yielded  in  any  degree  to  the  force 
of  the  muscles,  that  they  would  yield  more  and  more, 
and  be  ultimately  destroyed.  There  is  nothing  more 
admirable  in  the  living  frame  than  the  relation  esta« 


MECHANICAL  PROPERTIES  OF  BONE.  179 

blished  between  the  muscular  power  and  the  capacity 
of  passive  resistance  in  the  bones.  The  deviations 
from  the  cylindrical  forms  are  not  irregularities  ; and 
if  we  take  that  bone  which  deviates  the  furthest  from 
the  cylindrical  shape,  the  tibia,  or  shinbone,  we  shall 
have  demonstration  of  the  relation  between  the  shape 
of  the  bone  and  the  force  which  it  has  to  sustain. 

If  we  consider  the  direction  of  the  force  in  walking, 
running,  or  leaping,  and  in  all  the  powerful  exertions 
where  the  weight  of  the  body  is  thrown  forwards  on 
the  ball  of  the  great  toe,  it  must  appear  that  the  pres- 
sure against  this  bone  is  chiefly  on  the  anterior  part  : 
and  there  is  no  doubt  that  if  the  tibia  were  a perfect 
cylinder,  it  would  be  subject  to  fracture  even  with 
the  mere  force  of  the  body  itself  thrown  upon  it.  But 
if,  as  w’e  have  stated,  the  column  is  stronger  in  pro- 
portion as  the  material  is  distant  from  the  centre,  we 
readily  perceive  how  an  anterior  spine  or  ridge,  should 
be  thrown  out  : and  if  we  attend  to  the  internal  struc- 
ture of  that  spine,  we  shall  find  that  it  is  much  deirser 
and  stronger  than  the  rest  of  the  bone.  We  cannot 
here  deem  either  the  form  or  the  density  of  this  ridge, 
a thing  of  accident ; since  it  so  perfectly  corresponds 
with  the  experiment  of  Du  Hamel  which  we  have  de- 
scribed, where  the  dense  piece  of  wood  being  let  into 
the  piece  of  timber,  it  was  found  to  be  a means  of  resist- 
ing transverse  fracture.  If  we  proceed  with  the  know- 
ledge of  these  facts  to  the  examination  of  the  different 
bones  of  the  skeletoir,  we  shall  find  that  every  where 
the  form  has  a strict  relation  either  to  the  motion  to  be 
performed,  or  the  strain  to  which  the  bone  is  liable. 

In  comparing  the  true  bones  with  the  coverings  of 
the  insects,  we  observed  the  necessity  for  the  porous 
structure  of  the  former.  If  it  be  necessary  that  the 
bone  shall  be  very  dense,  it  will  no  longer  be  possessed 
of  the  power  of  re-union  or  reproduction  when  it 
breaks  : it  will  not  re-unite  upon  iDeing  fractured,  and 
if  exposed,  it  will  die.  Here,  then,  is  an  obvious  im- 
perfection. The  bones  of  animals  cannot,  in  this  man- 


180 


ILLUSTRATIONS  OF  THE 


ner,  be  made  capable  of  sustaining  great  weight,  with- 
out losing  a property  which  is  necessary  to  their  exis- 
tence— that  of  restoration  on  their  being  uijured. 
And  even  were  the  material  very  much  condensed,  it 
does  not  appear  that  the  phosphate  of  lime,  united  as 
it  is  with  the  animal  matter,  is  capable  of  sustaining 
any  great  weight  ; this  accorduigly  limits  the  size  of 
animals.  It  may,  perhaps,  countenance  the  belief 
that  animals  bear  a relation  in  their  size  and  duration 
of  life,  to  the  powers  and  life  of  man,  that  the  larger 
animals  have  existed  in  a former  condition  of  the 
world.  We  allude  only  to  such  animals  as  have  ex- 
tremities : for  with  respect  to  the  whale,  its  huge  bulk 
lies  out  supported  on  the  water.  The  iguanadon,  dis- 
covered by  Mr.  Mantell,  is  estunated  to  have  been 
seventy  feet  in  length,  and  to  have  had  extremities. 
But  the  thigh  and  leg  did  not  exceed  eight  feet  in 
length,  while  the  foot  extended  to  six  feet  ; a propor- 
tion, altogether,  which  implies  that  the  extremities 
assisted  the  animal  to  crawl,  rather  than  that  they 
were  capable  ofbearmg  its  weight,  as  the  extremities 
of  the  mammaUa.  However,  we  &id  that  in  the  lar- 
ger terrestrial  animals,  the  material  of  the  bones  is 
dense,  and  that  their  cavities  are  filled  up  : the  diame- 
ters of  those  of  the  extremities,  with  their  spines  and 
processes  being  remarkably  large.  Nothing  can  be 
conceived  more  clumsy  than  the  bones  of  the  mega- 
therium ; so  that  it  really  appears  that  nature  has 
exhausted  her  resources  with  respect  to  this  materi- 
al ; and  that  livmg  and  vascular  bone  could  not  be 
moulded  into  a form  to  sustain  the  bulk  and  weight 
of  an  animal  much  superior  to  the  elephant,  mastodon, 
and  megatherium.* 


* The  subject  may  be  illustrated  in  this  manner  : — “ A soft  stone 
“ projecting  from  a wail,  may  make  a stile  strong  enough  to  bear  a 
“ person’s  weight ; but  if  it  were  necessary  to  double  the  length  of  the 
“ stile,  the  thickness  must  be  more  than  doubled,  or  a freestone  sub- 
“ stituted ; and  were  it  necessary  to  make  tliis  freestone  project  twice 
“ as  far  from  the  wall,  even  if  doubled  in  thickness,  it  would  not  be 


MECHANICAL  PROPERTIES  OF  BONE. 


181 


With  regard  to  the  articulation  of  the  bones,  we 
cannot  mistake  the  reason  of  the  surfaces  of  contact 
being  enlarged.  In  machinery  it  is  found  that,  if 
the  pressure  be  the  same,  the  extension  of  the  sur- 
faces in  contact  does  not  increase  the  friction.  If,  for 
example,  a stone  or  u piece  of  timber,  of  the  shape  of 
a book  or  a brick,  should  be  laid  upon  a flat  surface, 
it  would  be  drawn  across  it  with  equal  facility,  wdie- 
ther  it  rested  upon  its  edge  or  upon  its  side.  The  fric- 
tion of  the  bones  which  enter  into  the  knee  joint  is 
not  increased  by  their  greater  diameter  : while  great 
advantages  are  gained ; the  ligaments  which  knit 
these  bones  give  more  strength  than  they  otherwise 
would,  and  the  tendons  which  run  over  them,  being 
removed  to  a distance  from  the  centre,  have  more 
power. 


THE  MUSCULAR  AND  ELASTIC  FORCES. 

The  muscular  power  is  contrasted  with  the  elastic, 
as  possessing  a living-  property  of  motion.  We  acqui- 
esce in  the  distinction,  since  the  muscular  fibre  ceases 
to  have  irritability  or  power  in  death,  while  elasticity 
continues  in  the  dead  part.  But  yet  there  is  a,  pro- 
perty of  elasticity  in  the  living  body  which  cannot  be 
retained  after  death.  To  illustrate  this  vre  shall  take 
the  instance  of  the  catgut  string  of  a harp.  Suppose 
that  the  string  is  screwed  tight,  so  as  to  vibrate  in  a 


“ strong  enough  to  bear  a proportioned  increase  of  weight : granite 
“ must  be  placed  in  its  stead  ; and  even  the  granite  would  not  be 
“ capable  of  sustaining  four  times  the  weight  which  the  soft  stone 
“■bore  in  the  first  instance.  In  the  same  way  the  stones  which  form 
“ an  arch,  of  a large  span,  must  be  of  the  hardest  granite,  or  their 
“ own  weight  tvould' crush  them.  The  same  principle  is  applicable 
“ to  the  bones  of  animals.  The  material  of  bone  is  too  soft  to  admit 
“ an  indefinite  increase  of  weight ; and  it  is  another  illustration  of 
“ what  w^as  before  stated,  that  there  is  a relation  established  through 
“ all  nature  ; that  the  very  animals  which  move  upon  the  surface  of 
“ the  earth  are  proportioned  to  its  magnitude,  and  the  gravitation  to 
“ its  centre.” — Animal  Mechanics. 

16 


182 


OF  ELASTIC  PARTS. 


given  time,  and  to  sound  the  note  correctly ; if  that 
string  be  struck  rudely,  it  is  put  out  of  tune  ; that  is, 
it  is  stretched  and  somewhat  relaxed,  and  no  longer 
vibrates  in  time.  This  does  not  take  place  in  the 
living  fibre  : for  here  there  is  a property  of  restoration. 
If  we  see  the  tuner  screwing  up  the  harp  string,  and 
with  difficulty,  and  after  repeated  attempts,  bringing 
it  to  its  due  tension, — tiffing  it  with  the  tuning  fork, 
and  with  his  utmost  acquired  skill  restoring  it  to  its 
former  elasticity,  we  have  a demonstration  of  how 
much  life  is  performing  in  the  fibres  of  the  animal 
frame,  after  every  effort  or  exertion ; and  the  more 
powerful  the  mechanical  parts  of  the  body  are,  the 
more  carefully  is  the  proper  tension  of  the  tendons, 
ligaments,  and  heart-cords  preserved.  Or  we  ma}’ 
take  the  example  of  a steel  sprmg.  A piece  of  steel, 
heated  to  a white  heat,  and  plunged  into  cold  water, 
acquires  certain  properties ; and  if  heated  again  to 
500  of  Fahrenheit,  it  is  very  elastic ; possessing 
what  is  called  a “ spring  temper,”  so  that  it  will 
recoil  and  vibrate.  But  if  this  spring  be  bent  in  a 
degree  too  much,  it  will  lose  part  of  its  elasticity. 
Should  the  parts  of  the  living  bod}",  on  the  other 
hand,  be  thus  used,  they  have  a power  of  restoration 
which  the  steel  has  not. 

If  a piece  of  fine  mechanism  be  made  perfect  by 
the  workman,  it  may  be  laid  by  and  preserved  ; but 
it  is  very  different  with  the  animal  body.  The  me- 
chanical properties  of  the  livmg  frame,  like  the  endow- 
ments of  the  mind,  must  not  lie  idle,  or  they  will  suf- 
fed  deterioration.  If,  by  some , misfortune,  a limb  be 
put  out  of  use,  not  onl}*  is  the  power  of  the  muscles 
rapidly  diminished,  which  every  one  will  acknow- 
ledge, but  the  property  of  resistance  is  destroyed;  and 
bones,  and  tendons,  and  ligaments  quickly  degene- 
rate.* 


* This  subject  is  illustrated  in  the  Essay  on  Animal  Mechanics, 
Part  II. 


A COMPARISON  OF  THE  EYE  WITH  THE  HAND. 

If  we  are  in  search  of  an  object  wliich  shall  excite 
the  highest  interest,  and  at  the  same  time  afford 
proofs  of  design  in  the  most  delicate  of  all  the  organs 
of  the  body,  we  naturally  turn  to  the  eye  : and  this 
organ  suits  onr  present  purpose  the  better,  that  we 
have  to  show  how  much  of  the  sense  of  vision  de- 
pends on  the  hand,  and  how  strict  the  analogy  is 
between  the  two  organs. 

From  the  time  of  Sir  Henry  Wotton  to  the  latest 
writer  on  light,  the  e5*e  has  been  a subject  of  admi- 
ration and  eulogv'.  But  I have  ventured,  on  a former 
occasion,*  to  say,  that  this  admiration  is  misplaced, 
while  it  is  given  to  the  Irall  of  the  e}'e  and  the  optic 
nerve  exclusively ; since  the  high  endowments  of 
this  oi'gan  belong  to  the  exercise  of  the  whole  eye, 
to  its  exterior  apparatus,  as  much  as  to  its  humours 
and  the  proper  nerve  of  vision.  It  is  to  the  muscu- 
lar apparatus,  and  to  the  conclusions  which  we  are 
enabled  to  draw  from  the  consciousness  of  muscular 
effort,  that  we  owe  that  sense  by  which  we  become 
familiar  with  the  form,  magnitude,  and  relations  of 
objects.  One  might  as  well  imagine  that  he  under- 
stood the  effect  and  uses  of  a theodolite,  on  estimat- 
ing the  optical  powers  of  the  glasses,  without  looking 
to  the  quadrant,  level,  or  plumb-line,  as  suppose  that 
he  had  learnt  the  whole  powers  of  the  e}'e  by  con 
fining  his  study  to  the  naked  ball. 

We  must  begin  our  observations  by  a minute  atten- 
tion to  the  structure  and  sensibility  of  the  retina. 
The  retina  is  the  internal  coat  of  the  eye  ; it  consists 
of  a delicate,  pulpy,  nervous  matter,  which  is  con- 
tained between  two  membranes  of  extreme  fineness, 
and  these  membranes  both  support  it  and  give  to  its 


* See  Philosophical  Transactions. 


184 


COMPARISON  OF  THE  EYE 


surfaces  a mathematical  correctness.  The  matter 
of  the  nerv^e,  as  well  as  these  supporting  membranes, 
are  perfectly  transparent,  during  life ; and  on  the 
axis  of  the  eye,  there  is  a small  portion  which  remains 
transparent,  when  the  rest  of  the  membrane  becomes 
opaque,  and  which  has  been  mistaken  for  a foramen,* 
or  hole  in  the  retina.  It  is  surprising,  that  mth  ail 
the  industry  which  has  been  employed  to  demonstrate 
the  structure  of  the  e}'e,  it  is  only  in  the  present  day 
that  a most  essential  part  of  the  retina  has  been  dis- 
covered— the  membrane  of  Mr.  Jacob.  From  ob- 
serving the  phenomena  of  vision,  and  especially  the 
extreme  minuteness  of  the  image  cast  upon  the  reti- 
na, I had  conceived  that  the  whole  nerve  was  not  the 
seat  of  vision,  but  only  one  or  other  of  its  surfaces. 
This  could  not  be  well  illustrated  until  the  exterior 
membrane  of  the  retina  was  demonstrated.  But 
now  we  see  that  this  membrane,  when  floated  in 
water  and  under  a magnif}dng  glass,  is  of  extreme 
tenuity,  and  its  smooth  surface  is  well  calculated  to 
correspond  with  the  exterior  surface  of  that  la3'er  of 
nervous  matter  which  is  the  seat  of  the  sense. 

The  term  I'etina  would  implj'  that  the  nerve  con- 
stitutes a net-work  : and  the  expressions  of  some  of 
our  first  modern  authorities  would  induce  us  to  be- 
lieve that  they  view  it  in  this  light,  as  corresponding 
with  their  hypothesis.  But  there  is  no  fibrous  tex- 
ture in  the  matter  of  the  nerve  ; although,  when  the 
retina  is  floated  and  torn  with  the  point  of  a needle, 
the  innermost  of  the  membranes  which  support  the 
nerve,  the  tunica  vasculosa  retinx,  presents  something 
of  this  appearance. 

Vision  is  not  excited  bj^  light  unless  the  rays  pene- 
trate through  the  transparent  retina  and  reach  the 
exterior  surface  from  within. 

It  is  well  known,  that  if  we  press  upon  the  eye- 
ball with  a ke\r  or  the  end  of  a pencil-case,  zones  of 


It  is  this  part  which  is  called  tlie  foramen  of  Soemmerring. 


WITH  THE  HAND. 


1S5 


light  are  excited.  The  perception  of  that  light  is, 
as  if  the  rays  came  in  a direction  opposite  to  the 
pressure.  We  may  say  that,  in  this  case,  the  effect 
of  the  pressure  is  assimilated  to  that  of  light ; and 
as  light  can  strike  the  part  of  the  nerve  which  is 
pressed,  only  by  coming  in  an  opposite  direction,  the 
zones  of  light  produced  by  the  mechanical  impidse 
appear  in  the  usual  direction  of  rays  impinging  upon 
this  part : and  consequently,  they  give  the  impres- 
sion of  their  source  being  in  the  opposite  quarter. 
Let  us  contrast  this  phenomena  with  the  following 
experiment.  Close  the  eyelids,  and  cover  them  with 
a piece  of  black  cloth  or  paper  which  has  a small 
hole  in  it ; and  place  this  hole,  not  opposite  to  the 
pupil,  but  to  the  white  of  the  eye  ; direct  a beam  of 
light  upon  the  hole  ; a person  will  see  this  light  in 
its  true  direction.  Why  should  there  be  in  these  two 
cases  a difference  in  the  apparent  place  from  which 
the  light  is  derived  1 were  it  not  that  the  rays  of  light 
directed  upon  the  eye-ball,  after  striking  upon  the 
retina,  pierce  through  it  and  through  the  humours  of 
the  eye,  and  impinge  upon  the  retina  on  the  opposite 
side.  This  explains  why  the  light  excited  in  the 
eye  shall  appear  to  come  from  different  quarters ; but 
it  does  not  explain  why  there  should  not  be  a double 
impression — why  the  beam  of  light  should  not  in- 
fluence the  retina  while  penetrating  it  in  the  first  in- 
stance, that  is  in  passing  through  it  from  without 
inwards,  as  well  as  when  it  has  penetrated  the  hu- 
mours and  strikes  upon  the  opposite  part  of  the  retina 
from  within  outwards. 

Another  fact,  which  has  surprised  philosophers,  is 
the  insensibility  of  the  optic  nerve  itself  to  light.  If 
it  be  so  contrived  that  the  strongest  beam  of  light 
shall  fall  upon  the  end  of  the  nerve  at  the  bottom  of 
the  eye,  where  it  begins  to  expand  into  the  delicate 
retina,  no  sensation  of  light  will  be  produced.  This 
ought  not  to  surprise  us,  if  I am  correct  in  my  state- 
ment that  the  gross  matter  of  the  nerve  is  not  the 


186 


COMPARISON  OF  THE  EYE 


organ  of  vision,  but  the  exterior  surface  of  it  only. 
In  the  extremity  of  the  optic  nerve  there  is,  of  course, 
no  posterior  surface ; and,  indeed,  nothing  can  better 
prove  the  distinct  office  of  the  nerve  as  contrasted 
with  the  expanded  retina,  than  this  circumstance, 
that  when  the  strongest  ray  of  light  strikes  into  the 
nerve  itself,  the  impression  is  not  received.  It  seems 
to  imply,  that  the  capacity  of  receiving  the  impres- 
sion, and  of  conveying  it  to  the  sensorium,  are  two 
distinct  functions. 

Is  not  this  opinion  more  consistent  with  the  phe- 
nomena than  what  is  expressed  by  one  of  our  first 
philosophers,  that  the  nerve,  at  its  extremity  towards 
the  eye,  forms  what  has  been  called  the  puncium  cce- 
cum,  and  is  insensible,  because  it  is  not  yet  divided  into 
those  almost  infinitely  minute  fibres  Avhich  are  fine 
enough  to  be  thrown  into  tremors  by  the  rays  of  light. 

Independently  of  this  punctum  coecmn,  rve  have 
to  observe  that  the  whole  surface  of  the  retina  is  not 
equall}’'  sensible  to  light.  There  is  a small  spot,  op- 
posite to  the  pupil  and  in  the  axis  of  the  e)'e,  which 
is  more  peculiarly  sensible  to  visual  impressions.  An 
attempt  has  been  made  to  ascertain  the  diameter  of 
this  spot ; and  it  is  said,  that  a ray  at  an  angle  of  five 
degrees  from  the  optic  axis,  strikes  exterior  to  this 
sensible  part.  But  rve  shall,  on  the  contrary,  see 
reason  to  conclude,  that  the  sensible  spot  is  not  limit- 
ed to  an  exact  circle,  that  it  is  not  regularh'  defined, 
and  that  the  sensibility,  in  fact,  is  increasing  to  the 
veiy  centre. 

Some  have  denied  the  existence  of  this  extreme 
sensibility  in  the  centre  of  the  retina,  attributing  the 
distinctness  of  the  vision  to  the  circumstance  of  the 
light  being  made  to  converge  through  the  influence 
of  the  humours,  more  correctly  to  this  point.  I shall, 
therefore,  show  how  impossible  vision  would  be,  Avere 
it  not  that  the  sensibility  of  the  retina  increases  gradu- 
ally from  its  utmost  circumference  to  the  point  which 
forms  the  axis  of  the  eye. 


WITH  THE  HAND. 


187 


We  see  objects  by  reflected  light,  at  the  very  in- 
stant that  direct  light  enters  the  eye.  As  the  im- 
pression bjf  the  direct  light  is  many  times  stronger  than 
the  reflected  rays  from  the  object,  the  vision  of  the 
object  would  be  destroyed  by  the  contrast,  Avere  there 
not  this  admirable  provision  in  the  retina,  that  the 
direct  light  shall  fall  upon  a part  less  sensible,  the  re- 
flected light  upon  a part  more  sensible.  If,  in  full 
day,  and  in  the  open  held,  the  eye  be  directed  south- 
■\vard,  the  rays  from  the  sun  enter  the  eye  at  the 
time  that  we  are  looking  to  certain  objects.  It  is  per- 
fectly clear,  that  if  the  sun’s  rays  struck  a part  of  the 
retina  as  sensible  as  the  spot  in  the  centre  or  axis,  it 
would  extinguish  all  secondary  impressions:  the  glare 
would  be  painfully  powerful,  as  when  we  look  direct- 
ly to  the  sun.  If  a momentary  glance  to  the  sun 
produce  a sensation  so  acute  that  ^ve  see  nothing  for 
some  time  after,  would  not  the  same  happen  were  the 
retina  equally  sensible  in  all  its  surface  1 A similar 
thing  takes  place  in  a chamber  lighted  with  candles ; 
we  do  not  see  the  person  immediately  on  the  other 
side  of  the  candle  : for  there  the  direct  light  interferes 
with  the  reflected  light,  effacing  the  slighter  impres- 
sion of  the  latter. 

We  perceive,  therefore,  that  if  the  retina  were 
equally  sensible  over  all  its  surface  we  could  not  see. 
Let  us,  then,  observe  how  we  do  actually  see,  and 
how’  the  organ  is  exercised.  There  is  a continual 
desire  of  exercising  the  sensible  spot,  the  pr^^per  seat 
of  vision.  When  an  impression  is  made  upon  the 
retina,  in  that  unsatisfactory  degree,  which  is  the 
effect  of  its  striking  any  part  but  the  centre,  there  is 
an  effort  made  to  direct  the  axis  towards  it,  or,  in 
other  words,  to  receive  the  rays  from  it  upon  the  more 
sensible  centre.  It  is  this  sensibility,  therefore,  con- 
joined with  the  action  of  the  muscles  of  the  eye-ball, 
which  produce  the  constant  searching  motion  of  the 
eye  ; so  that,  in  effect,  from  the  lesser  sensibility  of 
the  retina  generally,  arises  the  necessity  for  this  exer- 


188 


COMPARISON  OF  THE  EYE 


cise  of  the  organ  ; and  to  this  may  be  attributed  the 
high  perfections  of  it. 

This  faculty  of  searching  for  the  object  is  slowly 
acquired  in  the  child  : and,  in  truth,  the  motions  of 
the  eye  are  made  perfect,  like  those  of  the  hand  by 
slow  degrees.  In  both  organs  there  is  a compound 
operation  : — the  impression  on  the  nerve  of  sense  is 
accompanied  with  an  effort  of  the  will,  to  accommo- 
date the  muscular  action  to  it.  It  is  no  contradiction 
to  this,  that  the  faculty  of  vision  is  made  perfect  in 
the  young  of  some  animals  from  the  beginnmg  ; no 
more  than  the  instinct  of  the  duck,  when  it  runs  to 
the  water  the  moment  that  the  shell  is  broken,  con- 
tradicts the  fact  that  the  child  leams  to  stand  and 
walk  after  a thousand  repeated  efforts. 

Let  us  now  see  how  essential  this  searching  motion 
of  the  e)^e  is  to  vision.  On  coming  into  a room,  we 
see  the  whole  side  of  it  at  once — the  miiTor,  the  pic- 
tures, the  cornice,  the  chairs ; but  we  are  deceived  : 
being  unconscious  of  the  motions  of  the  eye,  and  that 
each  object  is  rapidly,  but  successively,  presented  to  it. 
It  is  easy  to  show,  that  if  the  eye  were  steady,  vision 
would  be  quickly  lost : that  all  these  objects,  which 
are  distinct  and  brilliant,  are  so  from  the  motion  of 
the  eye  ; that  they  would  disappear  if  it  were  other- 
wise. For  example,  let  us  fix  the  eye  on  one  point, 
a thing  difficult  to  do,  owing  to  the  veiy  disposition 
to  motion  in  the  eye  : but  by  repeated  attempts  we 
may  at  length  acquire  the  power  of  fixing  the  eye  to  a 
point ; and  when  we  have  done  so,  we  shall  find, 
that  the  whole  scene  becomes  more  and  more  obscure, 
and  finally  vanishes.  Let  us  fix  the  eye  on  the  cor- 
ner of  the  frame  of  the  principal  picture  in  the  room. 
At  first,  every  thing  around  it  is  distinct  ; in  a very 
little  time,  however,  the  impression  becomes  weaker, 
objects  appear  dim,  and  then  the  eye  has  an  almost 
incontrollable  desire  to  wander  ; if  this  be  resisted, 
the  impressions  of  the  figures  in  the  picture  first  fade  : 
for  a time,  we  see  the  gilded  frame : but  this  also 


WITH  THE  HAND. 


189 


becosiies  dim.  When  we  have  thus  far  ascertained 
the  fact,  we  change  the  direction  of  the  eye,  but  ever 
so  little,  and  at  once  the  whole  scene  is  again  perfect 
before  us. 

These  phenomena  are  consequent  upon  the  retina 
being  subject  to  exhaustion.  When  a coloured  ray 
of  light  impinges  continuously  on  the  same  part  of 
the  retina,  it  becomess  less  sensible  to  it,  but  more 
sensible  to  a ray  of  the  opposite  colour.  When  the 
eye  is  fixed  upon  a point,  the  lights,  shades,  and 
colours  of  objects  continuing  to  strike  upon  the  same 
relative  parts  of  the  retina,  the  nerve  is  exhausted : 
but  when  the  eye  shifts,  there  is  a new  exercise  of 
the  nerve  ; the  part  of  the  retina  that  was  opposed 
to  the  lights,  is  now  opposed  to  the  shades,  and  what 
was  opposed  to  the  difi’erent  colours  is  now  opposed 
to  other  colours,  and  the  variation  in  the  exciting 
cause  produces  a renewed  sensation.  From  this  it 
appears,  how  essential  the  incessant  searching  mo- 
tion of  the  eye  is  to  the  continued  exercise  of  the 
organ. 

Before  dismissing  this  subject,  we  may  give  ano- 
ther instance.  If  we  are  looking  upon  an  extensive 
prospect,  and  have  the  eye  caught  by  an  object  at  a 
distance,  or  when,  in  expectation  of  a friend,  we  see 
a figure  advancing  on  the  distant  road,  and  we  en- 
deavour to  scrutinize  the  object,  fixing  the  eye  in- 
tently upon  it,  it  disappears  ; in  our  disappointment 
we  rub  the  eyes,  cast  them  about,  look  again,  and 
once  more  we  see  the  object.  The  reason  of  this  is 
very  obvious : the  retina  is  exhausted,  but  becomes 
recruited  b)^  looking  on  the  other  objects  of  different 
shades  and  colours.  The  sportsman  on  the  moor  or 
the  hill  side,  feels  this  a hundred  times  when  he 
marks  down  his  covey,  fixing  his  eye  and  travelling 
towards  the  spot. 

Here  we  may  interrupt  our  inquiry  to  observe  how 
inconsistent  these  phenomena  are  with  the  favourite 
hypothesis— that  light  produces  vision  by  exciting 


190 


COMPARISON  OF  THE  EYE 


vibration  in  the  fibres  of  the  nerve.  By  all  the  laws 
of  motion  from  which  this  hypothesis  is  borrowed, 
we  know  that  if  a body  be  set  in  motion,  it  is  easU}^ 
kept  in  motion  ; and  that  if  a cord  vibrate,  that  vi- 
bration will  be  kept  up  by  a motion  in  the  same 
time.  It  appears  to  me  natural  to  suppose,  that  if 
these  fibres  of  the  nerve  (which,  be  it  remembered, 
are  also  imaginary)  were  moved  like  the  cords  of  a 
musical  instriunent,  they  would  be  most  easily  con- 
tinued in  motion  by  undulations  in  the  same  time : 
that  if  the  red  ray  oscillated  or  vibrated  in  a certain  pro- 
portion of  time,  it  would  keep  the  fibres  of  the  nerve 
in  action  more  easil)’^,  than  a green  ray,  which  vi- 
brates in  a different  time.  If  the  colour  of  a ray 
depended  upon  the  peculiar  undulation  or  vibration, 
it  appears  that  before  the  green  ray  could  produce  a 
motion  corresponding  with  itself,  it  must  encounter  a 
certain  opposition,  in  interrupting  the  motion  already 
begun.* 

* “Although  any  kind  of  impulse  or  motions  regulated  by  any 
“ law  may  be  transferred  from  molecule  to  molecule  in  an  elastic 
“ medium,  yet  in  the  theory  of  light  it  is  supposed  that  only  such 
“ primary  impulses,  as  recur  according  to  regular  periodical  laws 
“ at  equal  intervals  of  time  and  repeated  many  times  in  succession, 
“ can  affect  our  organs  with  the  sensation  of  light.  To  put  in  motion 
“ the  molecules  of  the  nerves  of  our  retina  with  sufficient  efficacy, 
“ it  is  necessary  that  the  almost  infinitely  minute  impulse  of  tlie 
“ adjacent  ethereal  molecules  should  be  often  and  regularly  repeated, 
“ so  as  to  multiply  and  concentrate  their  effect.  Thus,  as  a great 
“ pendulum  may  be  set  in  swing  by  a very  minute  force,  often  ap- 
“ plied  at  intervals  exactly  equal  to  its  tune  of  oscillation,  or  as  one 
“ elastic  body  can  be  set  in  vibration,  b}-  the  vibration  of  anotlier  at 
“ a distance  propagated  through  the  air,  if  in  exact  unison,  even  so 
“ we  may  conceive  the  gross  fibres  of  the  nerves  of  the  retina  to 
“ be  thrown  into  motion  by  the  continual  repetition  of  the  etliereal 
“ pulses  ; and  such  only  will  be  thus  agitated,  as  from  their  size, 
“ shape  or  elasticity,  are  susceptible  of  vibrating  in  times  exactly 
“ equal  to  those  at  which  the  impulses  are  repeated.  Thus  it  is  easy 
“ to  conceive  how  the  limits  of  visible  colour  may  be  established  : for 
“ if  there  be  no  nervous  fibres  in  unison  with  vibrations  more  or  less 
“ frequent  than  certain  limits,  such  ribrations,  though  they  reach  the 
“ retina,  will  produce  no  sensation.  Thus,  too,  a smgle  impulse,  or 
“ an  irregularly  repeated  one,  produces  no  fight.  And  thus  also 
“ may  the  vibrations  excited  in  the  retina  continue  a sensible  time  af- 


WITH  THE  HAND. 


191 


Reverting  to  the  sensible  spot  in  the  retina,  it  does 
not  appear  that  we  are  authorized  in  terming  it  a 
spot.  The  same  law  governs  vision  when  we  look  to 
a fine  point  of  a needle,  or  to  an  object  in  an  exten- 
sive landscape.  We  look  to  the  point  of  a pen,  and 
we  can  rest  the  attention  on  the  point  upon  the  one 
side  of  the  slit,  to  the  exclusion  of  the  other,  just  as 
we  can  select  and  intently  survey  a house  or  a tree. 
If  the  sensible  spot  were  regularly  defined,  it  must 
be  very  small : and  were  it,  indeed,  so  defined,  we 
should  be  sensible  of  it ; which  we  are  not.  The 
law,  therefore,  seems  to  be,  at  all  times,  that  the 
nearer  to  the  centre  of  the  eye,  the  greater  the  sen- 
sibility to  impression  ; and  this  holds  whether  we  are 
looking  abroad  in  the  country,  or  are  microscopically 
intent  upon  objects  of  great  minuteness. 

When  men  deny  the  fine  muscular  adaptation  of 
the  eye  to  the  sensation  on  the  retina,  how  do  they 
account  for  the  obvious  fact — that  the  eye-ball  does 
move  in  such  just  degrees  1 how  is  the  one  eye  ad- 
justed to  the  other  with  such  marvellous  precision!  and 
how  do  the  eyes  move  together  in  pursuit  of  an  object, 
never  failing  to  accompany  it  correctly,  be  it  the  flight 
of  a bird,  or  the  course  of  a tennis-ball,  or  even  of  a 
bomb-shell ! Is  it  not  an  irresistible  conclusion — that 
if  we  so  follow  an  object,  adjusting  the  muscles  of  the 
eye  so  as  to  present  the  axis  of  vision  successively  to 
it,  as  it  changes  place,  we  must  be  sensible  of  these 
motions  ! for  how  can  we  direct  the  muscles  unless 
we  be  sensible  to  their  action  ! The  C|uestion  then 
comes,  to  be — wliether  being  sensible  to  the  condition 
of  the  muscles,  and  being  capable  of  directing  them 
with  this  extraordinary  minuteness,  this  action  of  the 

“ ter  the  exciting  cause  has  ceased,  prolonging  the  sensation  of  light 
“ (especially  if  a vivid  one)  for  an  instant  in  the  eye  in  the  manner 
“ described.”  Sir  W.  Herschell,  Art.  Light.  Enc.  Met. 

Now  it  does  appear  to  me  that  this  reasoning  is  inconsistent  with 
the  phenomena  above  noticed. 


COMPARISON  OF  THE  EVE 


192 


muscles  does  not  enter  into  our  computation  of  tlie 
place  of  an  object  'I  But  is  not  this  exactly  the  same 
question  recurring  as  when  we  asked — whether  we 
can  direct  the  hand  without  knowing  where  the  hand 
is  1 Must  there  not  be  a feeling  or  knowledge  of  the 
position  of  the  hand,  before  we  can  give  it  direction  to 
an  object  'I  And  must  we  not  have  a conception  of 
the  relation  of  the  muscles  and  of  the  position  of  the 
axis  of  the  eye,  before  w^e  can  alter  its  direction  to  fix 
it  upon  a new  object  ] 

It  surprises  me  to  find  ingenious  men  refusing  their 
assent  to  the  opinion,  that  the  operation  of  the  mus- 
cles of  the  eye  is  necessary  to  perfect  vision,  when  the 
gradual  acquisition  of  the  power  maybe  seen  in  observ- 
ing the  awakening  sense  in  the  infant.  Mlren  a bright 
object  is  withdrawn  from  the  infant’s  eye,  there  is  a 
blank  expression  in  the  features  ; and  an  excitement 
when  the  object  is  again  presented.  For  a time,  the 
shifting  of  the  object  is  not  attended  with  the  search- 
ing action  of  the  eye  : but,  by  and  bye,  the  eye  fol- 
lows it  and  looks  around  for  it,  when  it  is  lost.  In 
this  gradual  acquisition  of  power  in  tire  eye,  there  is 
an  exact  parallel  to  the  acquisition  of  motion  in  the 
hand  ; and  in  both  instances,  we  seek  to  join  the  expe- 
rience obtained  by  means  of  the  muscular  motion  with 
the  impression  on  the  proper  nerve  of  sense. 

Some  maintain  that  our  idea  of  the  position  of  an 
object  is  implanted  in  the  mind  and  independent  of 
experience.  We  must  acknowledge  the  possibility  of 
this,  had  it  been  so  provided.  We  see  the  )'oung  of 
some  creatures  with  their  vision  thus  perfect  at  the 
moment  of  their  birth.  But  in  these  animals,  every 
corresponding  facult}'  is,  in  the  same  manner,  perfect 
from  the  beginning : the  dropped  foal,  oi  the  lamb, 
rises  and  follows  its  mother.  We  must  no  more  com- 
pare the  helpless  human  offspring  with  the  young  of 
these  animals  than  with  a fly,  the  existence  of  which  is 
limited  to  an  hour  at  noon, — which  breaking  from  its 
confinement,  knows  its  mate  and  deposits  its  eggs  on 


WITH  THE  HAND. 


193 


the  appropriate  tree — the  willow  or  the  thorn,  and  dies. 
But  this  is  foreign  to  our  enquiry  ; since  it  is  obvious 
that  the  human  eye  has  no  such  original  power  of 
vision  bestowed  upon  it,  and  that  it  is  acquired,  as  the 
exercise  of  the  other  senses,  and  the  faculties  of  the 
mind  itself  are,  by  repeated  efforts,  or  experience. 

if  it  be  admitted  that  the  ideas  which  v/e  receive 
through  the  eye  come  by  experience,  we  must  al- 
low that  the  mind  must  be  exercised  in  the  act  of 
comparison,  before  we  can  have  a conception  of  any 
thing  being  exterior  to  the  eye,  or  of  an  object  being 
placed  in  a particular  direction.  Authors  make  the 
matter  complex  by  conceiving  a picture  to  be  drawn 
at  the  bottom  of  the  eye,  and  presenting  to  us  the 
mind  contemplating  this  inverted  picture,  and  compa- 
ring the  parts  of  it.  But  this  leaves  the  subject  with- 
out any  explanation  at  all,  and  does  not  show  how  it 
is  that  the  mind  looks  into  this  camera.  The  question 
will  be,  at  least,  more  simple,  if  we  consider  the  vision 
of  a point ; and  ask  ourselves  how  we  know  the  di- 
rection in  which  that  point  comes  to  the  eye.  Sup- 
pose it  is  a star  in  the  heavens,  or  a beacon,  seen  by  tire 
mariner  ; must  he  not,  in  order  to  ascertain  the  po- 
sition of  the  star,  find  out  some  other  object  of  compari- 
son, some  other  star,  which  shall  disclose  to  him  tire 
constellation  to  which  the  one  that  he  is  examining 
belongs  : or  to  ascertain  the  position  of  the  beacon, 
must  he  not  look  to  his  compass  and  card,  and  so  trace 
the  direction  of  the  lighthouse  in  relation  to  them  1 
This  is,  in  fact,  the  process  that  is  followed  in  everj" 
thing  which  we  see.  A single  point  is  directly  in  the 
axis  of  the  eye,  but  we  cannot  judge  of  its  position, 
without  turning  to  some  other  point,  and  feeling 
«ensible  of  the  traversing  of  the  eye-ball  and  the  angle 
to  which  the  eye  is  moved  : or  if  we  do  not  see  another 
point  to  compare  the  first  with,  we  must  judge  of  its 
place  by  means  of  a comparison  with  the  motion  of 
the  eye  itself.  We  are  sensible  that  the  eye  is  di- 
rected to  the  right  or  to  the  left ; and  we  compare 
17 


194 


COMPARISON  OF  THE  EYE 


the  visible  impression  on  the  nerve  with  the  motion, 
its  direction,  and  its  extent. 

We  find  even  mathematicians  affinning  that  we 
judge  of  the  direction  of  an  object  by  the  ray  that  falls 
upon  the  retina.  But  the  ray  which  is  here  spoken 
of  strikes  a mere  point  of  the  retina  ; this  point  can 
have  no  direction  ; the  obliquity  of  the  incidence  of 
the  ray  can  inform  us  of  nothing  : rays  of  all  degrees 
of  obliquity  are  converging  to  form  that  point.  And 
do  not  the  same  mathematicians  give  us,  in  the  first 
lessons  of  their  science,  as  the  definition  of  a line, 
that  which  is  drawn  through  two  points  at  the  least  1 
Where  are  the  two  points  here  to  indicate  the  direc- 
tion of  the  line, — since  the  cornea,  or  the  humours  of 
the  eye,*  are  not  sensible  to  the  passage  of  the  ray  7 
Or  is  this  an  error  which  has  crept  in  from  inaccurate 
conceptions  of  the  anatomy  ? Has  the  idea  that  the 
direction  of  the  ray  can  afford  this  knowledge,  arisen 
from  the  notion  that  the  raj^  passes  through  the  thick 
and  turbid  matter  of  the  retina  7 I would  ask  for  what 
reason  is  the  “finder”  attached  to  the  great  telescope  7 
is  it  not  because  the  larger  instrument  from  magnify- 
ing one  object  in  a high  degree,  cannot  be  directed 
in  the  heavens,  the  observer  seeing  nothing  but  that 
one  object  1 Accordingly  to  remedy  this,  there  is 
mounted  on  the  greater  telescope  a smaller  one,  ex- 
actly parallel,  of  lesser  power,  but  commanding  a 
greater  field : this  finder,  the  astronomer  directs  to 
the  constellation  and  moves  from  star  to  star,  until 
that  which  he  desires  to  examine  is  in  the  centre  of 
the  field  ; and  by  this  means  he  adjusts  the  larger 
telescope  to  his  object.  Is  this  not  a correct  illustra- 
tion of  the  operation  of  the  eye  7 is  the  eye  not  im- 
perfectly exercised  when  it  sees  but  one  point — on 
the  other  hand,  is  it  not  in  the  full  performance  of  its 
function  when  it  moves  from  one  object  to  the  other, 


* See  a paper  by  Mr.  Alexander  Shaw,  who  has  explained  this 
subject  very  happily. — Journal  ot  the  Royal  Institution,  1832. 


WITH  THE  HAND. 


195 


judges  of  the  degree  and  the  direction  of  that  motion, 
and  thus  enables  us,  by  comparison,  to  form  our  judg- 
ment 1 

It  has  been  stated  by  a most  ingenious  philosopher 
of  our  own  time,  that  the  forms  and  relations  of  ob- 
jects are  known  to  us  by  the  unassisted  operation  of 
the  eye-ball  itself — by  the  transmission  of  the  rays 
through  the  humours  of  the  eye,  and  by  their  effect 
upon  the  retina  ; and  he  has  also  affirmed  that  we 
should  know  the  position  of  objects  even  if  the  muscles 
of  the  eye  were  paralytic.  But  I hope  that  it  has 
been  understood,  when  I give  so  much  importance  to 
the  motions  of  the  eye,  that  I do  not  neglect  the 
movements  of  the  body,  and,  more  especially,  the 
motions  of  the  hand  : that,  in  truth,  the  measure  of 
objects  which  we  take  through  the  eye,  is  in  corres- 
pondence with  the  experience  which  Ave  have  had 
through  the  motions  of  the  whole  frame,  and  that, 
without  such  experience,  we  should  have  no  know- 
ledge of  matter,  or  of  position,  or  of  distance,  or  of 
form.  W ere  the  eye  fixed  in  the  head,  or  paraJytic, 
we  should  lose  a great  part  of  the  exercise  of  the 
organ,  as  AA^ell  as  all  the  appliances  Avhich  are  neces- 
sary for  its  protection  ; but  Ave  should  still  be  capable 
of  comparing  the  Ausual  impression  AAdth  the  experi- 
ence of  the  body.  As  long  as  Ave  know  the  right 
hand  from  the  left,  or  must  raise  our  head  to  see  Avhat 
is  above  us,  or  stoop  to  see  a man’s  foot,  there  can  be 
no  Avant  of  materials  to  form  a comparison  betAveen 
the  impression  on  the  nerve  of  sight  and  the  experi- 
ence of  the  body. 

Against  this  vieAV  of  the  compound  operation  of 
the  eye,  the  matter  is  thus  argued  ; — if  a man  receive 
the  impression  of  a luminous  body  upon  his  eye  so 
that  the  spectrum  shall  remain  Avhen  the  eye -lids 
are  shut,  and  if  he  be  seated  upon  a stool  that  turns 
round,  and  he  be  Avhirled  round  by  the  hand  of  a 
friend,  Avithout  his  OAvn  effort,  the  motion  of  the  spec- 
trum Avill  correspond  Avith  his  OAvn.  No  doubt  it 


196 


COMPARISON  OF  THE  EYE 


will : because  he  is  conscious  of  being  turned  round  : 
a man  cannot  sit  upon  a stool  that  is  turning  without 
an  effort  to  keep  his  place,  without  a consciousness  of 
being  turned  round ; and  feeling,  at  the  same  time, 
that  the  impression  is  still  before  his  eye,  he  will  see 
the  spectrum  before  him,  and  in  that  aspect  to  which 
he  has  been  revolved. 

Were  I not  conscious  that  I am  right,  I should  feel 
it  necessary  to  make  an  apology  for  differing  from 
eminent  men  on  this  matter  : but  I conceive  the 
explanation  of  this  discrepancy  to  be,  that  we  are  veiy 
much  influenced  by  the  manner  in  which  we  approach 
to  the  examination  of  such  a subject.  A man  lost  in 
admiration  of  the  properties  of  light,  and  of  the  effect 
of  the  humours  of  the  eye  as  an  optical  instrument, 
may  be  blinded  to  those  inferences,  which  to  me  seem 
so  undeniable,  accustomed  as  I have  been  to  compare 
the  properties  of  the  eye  with  the  living  endowments 
of  the  frame.  When  instead  of  looking  upon  the  eye 
as  a mere  camera  or  show  box,  with  the  picture 
inverted  on  the  bottom,  we  determine  the  value  of 
muscular  activity  ; mark  the  sensation  attending  the 
balancing  of  the  Irody  ; that  fine  property  which  we 
possess  of  adjusting  the  muscular  frame  to  its  various 
inclinations  ; how  it  is  acquired  in  the  child  ; how  it 
is  lost  in  the  paralytic  and  drunkard  ; how  motion 
and  sensation  are  combined  in  the  hand ; how,  in 
this  way,  the  hand  guides  the  finest  instruments  ; 
when  we  consider  how  the  eye  and  the  hand  cor- 
respond ; how  the  motions  of  the  eye,  combinmg  with 
the  impression  on  the  retina,  become  the  means  of 
measuring  and  estimating  the  place,  form  and  dis- 
tance of  objects — the  sign  in  the  eye  of  what  is 
known  to  the  hand : finally,  when,  by  attention  to 
the  motions  of  the  eye,  we  are  aware  of  their  extreme 
minuteness,  and  how  we  are  sensible  to  them  in  the 
finest  degree — the  conviction  irresistibly  follows,  that 
without  the  power  of  directing  the  eye,  (a  motion 
holding  relation  to  the  action  of  the  whole  body)  our 


WITH  THE  HAND. 


197 


finest  organ  of  sense,  Avliich  so  largely  contributes  to 
the  developement  of  the  powers  of  the  mind,  would 
lie  unexercised. 

THE  MOTION  OF  THE  EYE  CONSIDERED  IN  REGARD 

TO  THE  EFFECT  OF  SHADE  AND  COLOUR  IN  A PIC- 
TURE. 

A QUESTION  naturally  arises  whether  it  be  possible, 
from  this  part  of  philosophy,  to  suggest  some  princi- 
ples for  the  amateur  and  painter.  The  ideas  and  lan- 
guage of  the  amateur,  when  he  attempts  to  establish 
rules  for  the  disposition  of  colours  or  shades  in  a pic- 
ture, are  certainly  very  vague. 

We  have  to  remark,  in  the  first  place,  that  the  co- 
lours of  nature,  and  those  of  objects  when  represented 
in  a painting,  differ  in  most  essential  circumstances. 
Bodies  of  various  colours,  when  placed  together,  have 
their  colours  reflected  from  the  one  to  the  other  ; and 
so  thev  are  sent  to  the  e)"e.  This  is  one  mode  in 
Avhich  the  lines  of  nature  are  harmonized  ; but  the 
colours  upon  the  flat  surface  of  the  canvass  cannot  be 
thus  reflected  and  mingled.  The  next  difference  re- 
sults from  the  atmosphere,  through  which  the  rays 
from  distant  objects  proceed  to  the  eye  and  are  soften- 
ed ; the  canvass  being  near  the  eye,  the  effect  which 
the  atmosphere  produces  on  colours  amounts  to  no- 
thing in  the  picture.  The  third  mode  in  which  co- 
lours are  affected,  is  common  to  natural  objects  and 
to  paintings,  and  is  connected  with  the  law  of  vision 
which  we  have  been  considering,  and  to  which  we 
must  now  revert. 

When  we  make  experiments  by  looking  upon  co- 
loured spots,  the  effect  on  the  sensibility  of  the  retina 
is  remarkable  ; and  as  this  does  not  occur  incidentally, 
but  takes  place,  more  or  less,  whenever  we  exercise 
the  eye,  it  must  have  its  influence  when  we  look  to 
works  of  art.  The  familiar  fact  which  we  have  to 
carry  with  us  into  this  enquiry,  is,  that  if  we  throw  a 
17* 


198 


COMPARISON  OF  THE  EYE 


silver  coin  upon  a dark  table,  and  fix  the  e)'e  upon  the 
centre  of  it,  when  we  remove  the  coin  there  is,  for  a 
moment,  a white  spot  in  its  place,  which  presently  be- 
comes deep  black.  If  we  put  a red  wafer  upon  a sheet 
of  paper,  and  look  upon  it,  and  continue  to  keep  the 
eye  fixed  on  the  same  point,  upon  removing  the  wafer, 
the  spot  where  it  lay  on  the  white  paper  will  appear 
green.  If  we  look  upon  a green  wafer  in  the  same 
manner  and  remove  it,  the  spot  will  be  red  ; if  upon 
blue  or  indigo,  the  paper  will  appear  j-ellow.  These 
phenomena  are  to  be  explained  by  considering  that 
the  nerve  is  exhausted  by  the  continuance  of  the  im- 
pression, and  becomes  more  apt  to  receive  sensation 
from  an  opposite  colour.  All  the  colours  of  the  prism 
come  into  the  eye  from  the  surface  of  the  paper  when 
the  wafer  has  been  removed  ; but  if  the  nerve  has  been 
exhausted  by  the  incidence  of  the  red  rays  upon  it,  it 
will  be  insensible  to  these  red  rays  when  they  are  thus 
reflected  from  the  paper  ; the  effect  of  the  rays  of  an 
opposite  kind  will  be  increased,  and  consequently  the 
spot  will  be  no  longer  white,  but  of  the  prevailing 
green  colour. 

Let  us  see  how  the  loss  of  sensibility  produces  an 
effect  in  engraving,  wiiere  there  is  no  colour,  and 
only  light  and  shade. 

Is  it  possible  that  a high  tow-er,  in  a cloudless  sky, 
can  be  less  illuminated  at  the  top  than  at  the  bottom  ? 
let  if  we  turn  to  a book  of  engravings,  where  an  old 
steeple  or  tower  is  represented  standing  up  against 
the  clear  sky,  we  shall  find  that  all  the  higher  part  is 
dark,  and  that  the  effect  is  picturesque  and  pleasing. 
Now  this  is  perfectly  correct,  for  although  the  highest 
part  of  the  tower  be  in  the  brightest  illumination,  it 
is  not  seen  so — it  never  appears  so  to  the  e3*e.  The 
reason  is,  that  w'hen  we  look  to  the  steeple,  a great 
part  of  the  retina  is  opposed  to  the  light  of  the  sky  , 
and  on  shifting  the  e}^e  to  look  at  the  particular  parts 
of  the  steeple,  the  reflected  light  fi'om  that  object 
falls  upon  the  retina,  where  it  is  exhausted  by  the 


WITH  THE  HAND. 


199 


direct  light  of  the  sky.  If  we  look  to  the  top  of  the 
tower,  and  then  drop  the  eye  to  some  of  the  lower 
arcliitectural  ornaments,  the  effect  infallibly  is  that 
the  upper  half  of  the  tower  is  dark.  For  example,  if 


looking  to  the  point  A we  drop  the  eye  to  B : the 
tower  from  A to  B is  seen  by  that  part  of  the  retina 
which  was  opposed  to  the  clear  sky  from  A to  C ; 
and  it  is  dark  not  by  contrast,  as  it  w^ould  be  thought- 
lessly said,  but  by  the  nerve  being  somewhat  exhaust- 
ed of  its  sensibility.  This,  then,  is  the  first  effect  tve 
shall  remark  as  arising  from  the  searching  motion  of 
the  eye. 

The  refreshing  colours  of  the  natural  landscape  are 
at  no  time  so  pleasing  as  when  reading  on  a journey, 
we  turn  tlie  eye  from  the  book  to  the  fields  and  woods ; 
tile  shadows  are  then  deeper — the  greens  more  sooth- 
ing, and  the  whole  colours  are  softened.  Reynolds 
observed  to  Sir  George  Beaumont  that  the  pictures 


200 


COMPARISON  OF  THE  EYE 


of  Rubens  appeared  different  to  him,  and  less  bril- 
liant, on  his  second  visit  to  the  continent ; and  the 
reason  of  the  difference  he  discovered  to  be  that,  on 
the  first  visit,  he  had  taken  notes,  and  on  the  second 
he  did  not.  The  alleged  reason  is  quite  equal  to  the 
effect ; but  I cannot  help  imagining  that  there  is 
some  incorrectness  in  the  use  of  the  term  brilliant, 
unless  warmth  and  depth  of  colouring  is  meant,  for 
when  the  eye  turns  from  the  white  paper  to  the  paint- 
ing, the  reds  and  yellows  must  necessarily  be  deeper. 
If  we  look  out  from  the  window,  and  then  turn 
towards  a picture,  the  whole  effect  is  gone — the 
reflected  rays  from  the  picture  are  too  feeble  to  pro- 
duce their  impression  ; and  if  we  look  upon  a sheet 
of  paper,  and  then  upon  a picture,  the  tone  will  be 
deeper,  and  the  warm  tints  stronger,  but  the  lights 
and  shades  less  distinct.  If  we  place  an  oil  painting 
without  the  frame,  upon  a large  sheet  of  paper,  or 
against  a white  plastered  wall,  it  is  offensively  yellow. 
Here  the  eye  alternately,  though  insensibly,  moving 
from  the  white  paper  or  wall  to  the  painting,  which 
is  of  a deep  tone,  the  browns  and  yellows  are  unnatu- 
rally strong.  We  see  the  necessity  or  the  effect  of 
the  gilt  frame  for  such  a picture  : it  does  not  merely 
cut  off  surrounding  objects,  but  it  prepares  the  eye 
for  the  colours  of  the  painting — it  allows,  if  I may  so 
express  it,  the  painter  to  use  his  art  more  boldly,  and 
to  exaggerate  the  colours  of  nature. 

Painters  proceed  by  experiment.  If  they  are  paint- 
ing a portrait,  the}^  may  represent  the  features  by 
contrasts  of  lights  and  shadows  with  very  little  co- 
lour ; but  such  a portrait  is  never  popular.  If  they 
are  to  represent  the  features  without  much  contrast 
of  light  and  shade,  they  must  raise  the  features  by 
contrasts  of  colours,  and  the  carnations  are  necessarily 
exaggerated  ; but  all  this  is  softened  down  by  throw- 
ing a piece  of  drapery  into  the  picture,  the  colours  of 
which  so  prepare  the  e}'e  that,  now  looking  on  the 
features,  that  will  appear  natural,  which,  but  for  this 


WITH  THE  HAND. 


201 


art,  would  have  represented  an  inflamed  countenance. 
The  common  resource  of  the  painter  is  to  throw  in  a 
crimson  curtain,  or  to  introduce  some  flower  or  piece 
of  dress,  that  shall  lead  the  eye,  by  a succession  of 
tints,  or,  more  accurately  speaking,  shall  prepare  the 
eye  to  receive  the  otherwise  exaggerated  colours  of 
the  portrait.  The  eye  cast  on  the  red  curtain,  and 
then  falling  on  the  countenance,  sees  it  as  if  coloured 
onl}'^  with  the  modesty  of  nature. 

Those  who  hang  pictures,  do  not  place  an  histori- 
cal picture,  painted  after  the  manner  of  the  Bolognese 
school  with  distinct  and  abrupt  coloured  draperies,  by 
the  side  of  a landscape  ; for  the  colours  of  a landscape, 
to  be  at  all  consonant  with  nature,  are  weak  and 
reduced  to  a low  tone,  by  representing  that  effect, 
which  we  observed,  of  the  intervention  of  the  atmos- 
phere. The  colours,  therefore,  would  be  destro)'ed 
by  too  powerful  a contrast.  There  is  a difficulty  of 
deciding  what  should  be  the  colour  of  the  walls  of  a 
gallery,  because  the  pictures  are,  for  the  most  part, 
painted  on  different  principles  ; but  generally  speak- 
ing, the  dark  subdued  red  or  morone  colour  brings 
out  the  colours  of  paintings  ; in  other  words,  if  we 
look  on  a wall  of  this  colour,  and  then  turn  to  the 
picture,  the  prevailing  green  and  yellow  tints  will 
appear  brighter. 

The  word  “ contrast”  is  used  without  a definition,  or 
without  the  actual  comprehension  of  what  it  means. 
Now  the  effect  of  colours,  on  being  placed  together,  is 
produced  through  the  motionoi the  eye,  combined  with 
this  law  of  the  sensibility  of  the  retina,  which  wehave 
been  adverting  to.  When  v/e  imagine  that  we  are  com- 
paring colours,  we  are  really  experiencing  the  effect  of 
the  nerve  being  exhausted,  by  dwelling  on  one  colour, 
and  made  more  susceptible  of  the  opposite  colour.  In 
coloured  drapery,  for  example,  there  is  such  a mixture 
of  all  colours  reflected  from  it,  although  one  prevails, 
that  the  impression  may  be  greatly  modified  by  what 
the  eye  has  previously  experienced.  If  the  colouring  of 


202 


COMPARISON  OF  THE  EYE 


the  flesh  be,  as  the  painter  terms  it,  “too  warm,”  it 
may  be  made  “ cold”  by  rendering  the  eye  insensi- 
ble to  the  red  and  yellow  rays,  and  more  than  usually 
susceptible  of  the  blue  and  purple  rays.  Everj*  co- 
loured ray  from  the  flesh  is  transmitted  to  the  eye  ; 
but  if  the  eye  has  moved  to  it  from  a yellow  or  crimson 
drapery,  then  the  rays  of  that  kind  will  be,  for  the 
moment,  lost  to  the  vision,  and  the  colour  of  the  flesh 
will  appear  less  warm,  in  consequence  of  the  preva- 
lence of  the  opposite  rays  of  colour. 

It  ought  to  be  unsatisfactory  to  the  philosophical 
student  to  make  use  of  a term  without  knowing  its  full 
meaning.  There  has  been  a great  deal  said  about 
contrast  and  harmony  in  painting,  as  residting  from 
certain  colours  placed  together — the  idea  being  that 
we  see  these  colours  at  the  same  time — whereas,  the 
effect,  of  which  we  are  all  sensible,  results  from  alter- 
nately looking  at  the  one  and  at  the  other.  The 
subject  might  be  pleasantly  pursued,  but  I mean  only 
to  vindicate  the  importance  of  the  motions  of  the  eye 
to  our  enjo5unent,  whether  of  the  colours  of  art  or  of 
nature.  There  is  another  subject  of  some  interest, 
namely,  the  effect  produced  upon  the  retina  when  the 
eye  is  intently  fixed  upon  an  object,  and  is  not  pennit- 
ted  to  wander  from  point  to  pomt.  This  touches  the 
chiaroscuro  of  painting  ; which  is  not  merely  the 
managing  of  the  lights  and  shadows,  but  the  preserv- 
ing of  the  parts  of  a scene  subordinate  to  the  principal 
object.  There  is  something  unpleasant  and  imper- 
fect, even  to  the  least  experienced  eye,  in  a picture  in 
which  every  tiung  is  made  out — the  drapery  of  every 
figure,  the  carving  or  ornament  of  every  object  minute- 
Ij'  represented  ; for  these  things  were  never  so  seen  in 
nature.  The  true  picture,  on  the  other  hand,  is  effec- 
tive, and  felt  to  be  natural,  when  the  eye  is  at  once 
led  to  dwell  on  that  principal  group,  or  principal  figure, 
with  which  it  is  the  artist’s  intention  to  occupy  the 
imagination.  fine  mastery  of  his  art,  and  by  in- 
sensible degrees,  the  painter  keeps  down  the  parts 


WITH  THE  HAND. 


203 


which  are  removed  from  the  centre  ; and  thus  he 
represents  the  scene  as  when  we  look  intently  upon 
an  object — seeing  that  which  is  near  the  axis  of  the 
eye  distinctly — the  other  objects,  as  it  were,  retreating 
or  rising  out  less  and  less  distinctly,  in  proportion  as 
they  recede  from  the  centre.  In  the  one  instance,  the 
artist  paints  a panorama,  where  w*e  turn  round  and 
have  presented  before  the  eye  the  several  divisions  of 
the  circle,  in  each  of  which  the  objects  are  equally 
distinct ; in  the  other,  he  paints  a picture  representing 
things,  not  as  when  the  eye  wanders  from  the  one  part 
to  the  other,  but  where  it  is  fixed  with  higher  interest 
upon  some  central  object,  while  the  others  fall  ofi’ 
subordinately. 

Looking  to  our  main  argument,  the  proofs  of  bene- 
ficence in  the  capacities  of  the  living  frame,  we  revert 
naturally  to  the  pleasures  received  through  this  double 
property  of  the  eye — motion  and  sensibility  ; and 
whilst  we  perceive  that  the  varieties  of  light  and  shade 
are  necessary  to  vision,  we  find  that  the  coloured  rays 
are  also,  by  variety,  suited  to  the  higher  exercise  of 
this  sense.  They  do  not  all  equally  illuminate  objects, 
nor  are  they  all  equally  agreeable  to  the  eye.  The 
yellow,  pale  green,  or  Isabella  colours,  illuminate  in 
the  highest  degi’ee,  and  are  the  most  agreeable  to  the 
sense  ; and  we  cannot  but  observe,  on  looking  out  on 
the  face  of  nature,  that  they  are  the  prevailing  co- 
lours.* The  red  ray  illuminates  the  least,  but  it  irri- 
tates the  most ; and  it  is  this  variety  in  the  influence 
of  these  rays  upon  the  nerve  that  continues  its  exer- 
cise, and  adds  so  much  to  our  enjoyment.  We  have 
pleasure  from  the  succession  and  contrast  of  colours, 
independently  of  that  higher  gratification  which  the 
mind  enjoys  through  the  influence  of  association. 


* The  astronomer  selects  a glass  for  his  telescope,  which  refracts 
the  pale  yellow  light  in  the  greatest  proportion,  because  it  illuminates 
In  the  highest  degree  and  irritates  the  least. 


ADDITIONAL  ILLUSTRATIONS  TO  THE  CONCLUDING 
CHAPTER. 

I HAVE  sometimes  thought  it  possible,  that  a great- 
ly extended  survey  of  nature  ma}^  humble  too  much 
our  conceptions  of  ourselves  ; and  that  this  requires  to 
be  corrected  by  the  study  of  things  more  minute,  and 
in  which  we  are  more  directlj"  concerned  : by  dwel- 
ling on  the  perfection  of  the  frame  of  the  animal  body 
and  the  marvellous  endowments  of  the  living  proper- 
ties. Wlien  we  have  formed  some  estimate  of  the 
immensity  of  the  heavenly  bodies,  we  are  struck 
with  admiration  in  following  the  successive  advance- 
ment made  in  the  science  : — an  improvement  in  the 
curves  of  the  glasses  of  the  telescope,  a new  mode  of 
polishing  the  reflecting  surfaces,  a change  in  the 
chemical  composition  of  the  glasses,  or  a more  per- 
fect adjustment  of  their  dispersive  powers — is  follow- 
ed by  the  discovery  of  circle  be}'ond  circle  of  worlds 
interminabl3^ 

We  fan  the  imagination  and  labour  to  comprehend 
the  immensity  of  the  creation,  and  fall  back  with  the 
impression  of  the  littleness  of  all  that  belongs  to  us : 
our  lives  seem  but  a point  of  time,  compared  witli  the 
astronomical  and  geological  periods,  and  we  ourselves 
as  atoms,  driven  about,  amidst  unceasing  changes  of 
the  material  world. 

But  it  has  been  shown,  that  whether  we  take  the 
animal  body  as  a single  machine,  or  embrace  in  the 
survey  the  successive  creation  of  animals,  conforming 
always  to  the  improving  condition  of  the  earth,  there 
is  nothing  like  chance  or  irregularity  in  the  composi- 
tion of  the  system.  In  proportion  indeed  as  we  com- 
prehend the  principles  of  mechanics,  or  of  hydi-aulics. 


ADDITIONAL  ILLUSTRATIONS,  &C.  205 

as  applicable  to  the  animal  machinery,  we  shall  be 
satisfied  of  the  perfection  of  the  design  : and  if  any 
thing  appear  disjointed  or  thrown  in  by  chance,  let 
the  student  mark  that  for  contemplation  and  experi- 
ment, and  most  certainly  when  it  comes  to  be  under- 
stood, other  parts  will  receive  the  illumination,  and 
the  whole  design  stand  more  fully  disclosed. 

The  extension  of  knowledge  has  not  irecessarily 
the  effect  of  raising  the  mind  to  more  consolatory  con- 
templations. We  may  quote  the  ancient  philosopher 
in  contrast  with  the  modern.  The  former  having  no- 
thing in  his  mind  to  draw  him  from  observing  the 
just  relations  of  human  beings  to  the  world  ; but  on 
the  contrary,  seeing  every  thing  suited  to  man  or  sub- 
ordinate, thinks  of  him  “as  a little  God  harboured  in  a 
humane  body.”  But  when  by  science,  and  the  aid 
of  instruments,  or  “the  ingenuity  of  the  hand,”  vision 
is  extended  to  things  too  remote  perhaps,  or  too  mi- 
nute, to  fall  within  our  natural  sphere  ; when  instead 
of  the  extended  plane,  and  visible  horizon  of  the  sta- 
ble earth,  it  is  thought  of  as  a ball  rolling  through 
space,  amidst  myriads  besides,  greater  than  it : the 
expression  is  excusable  that — “ the  earth  with  man 
upon  it  does  not  seem  much  other  than  an  ant-hill, 
where  some  ants  carry  corn,  and  some  carry  their 
young,  and  some  go  empty,  and  all  to  and  fro,  a lit- 
tle heap  of  dust.” 

We  may  consider  man,  before  the  lights  of  modern 
philosophy  had  their  influence  on  his  thoughts,  as  in 
a state  more  natural ; in  as  much  as  he  yielded  unre- 
sistingly to  those  sentiments  which  directly  flow  from 
the  objects  and  phenomena  arbundhim.  But  when 
that  period  of  society  arrived,  in  which  man  made  na- 
tural phenomena  the  subjects  of  experiment  or  of  phi- 
losophical enquiry,  then  was  there  some  danger  of  a 
change  of  opinion,  not  always  beneficial  to  his  state  of 
mind.  This  danger  does  not  touch  the  philosopher  so 
much  as  the  scholar.  He  who  has  strength  of  mind 
and  ingenuity  enough  to  make  investigations  into 
18 


206 


ADDITIONAL  ILLUSTRATIONS 


nature,  will  not  be  satisfied  with  the  discovery  of  secon- 
dary causes — his  mind  will  be  enlarged,  and  the  sub- 
jects of  his  thoughts  and  aspirations  become  more  ele- 
vated. But  it  is  otherwise  with  those  not  themselves 
habituated  to  investigation,  and  who  learn  at  second- 
hand, the  result  of  those  enquiries.  If  such  a one  sees 
the  fire  of  heaven  brought  down  into  a phial,  and  the 
materials  compounded,  to  produce  an  explosion  louder 
than  the  thunder,  and  ten  times  more  destructive,  the 
storm  will  no  longer  speak  a language  to  him.  Those 
influences  which  are  natural  and  just,  and  beneficently 
provided,  and  have  served  to  develope  the  sentiments 
of  millions  before  him,  are  dismissed  as  things  vulgar 
and  to  be  despised. — Yet  with  all  the  pride  of  newly 
acquired  knowledge,  his  conceptions  embarrass,  if 
they  do  not  mislead  him  ; in  short,  he  has  not  had  that 
intellectual  discipline,  which  should  precede  and  ac- 
company the  acquisition  of  knowledge. 

But  a man,  possessed  of  genius  of  the  highest  order, 
may  lose  the  just  estimate  of  himself,  from  another 
cause.  The  sublime  nature  of  his  studies  may  con- 
sign him  to  depressing  thoughts.  He  maj'  forget  the 
very  attributes  of  his  mind,  wliich  have  privileged  these 
high  contemplations,  and  the  ingenuity  of  the  hand, 
which  has  so  extended  the  sphere  of  his  observa- 
tion. 

The  remedy,  to  such  a mind,  is  in  the  studies  which 
we  are  enforcing.  The  heavenly  bodies,  in  their 
motions  through  space,  are  held  in  their  orbits  by  the 
continuence  of  a power,  not  more  wonderfid  nor  more 
deserving  of  admiration,  than  that,  by  which  a globule 
of  blood  is  suspended  in  the  mass  of  fluids  : — or  by 
which,  in  due  season,  it  is  attracted  and  resolved  : 
than  that,  by  which  a molecule  entering  into  the  com- 
position of  the  body,  is  driven  through  a circle  of  revo- 
lutions, and  made  to  undergo  different  states  of  aggre- 
gation; becoming  some  time,  apart  of  a fluid,  sometime, 
an  ingredient  of  a solid  ; — and  finally  cast  out  again, 
from  the  influence  of  the  living  forces. 


TO  THE  CONCLUDING  CHAPTER. 


207 


Our  argument  in  the  early  part  of  the  volume,  has 
shown  man,  by  the  power  of  the  hand  (as  the  ready 
instrument  of  the  mind)  accommodated  to  every  con- 
dition through  which  his  destinies  promise  to  be  ac- 
complished. We  first  see  the  hand  ministering  to  his 
necessities,  and  sustaining  the  life  of  the  individual : — 
a second  stage  of  his  progress,  we  see  it  adapted  to 
the  wants  of  society,  when  man  becomes  a labourer 
and  an  artificer.  In  a state  still  more  advanced, 
science  is  brought  in  aid  of  mechanical  ingenuity. 
The  elements  which  seemed  adverse  to  the  progress 
of  society,  become  tire  means  conducing  to  it.  The 
seas  which  at  first  set  limits  to  nations,  and  grouped 
mankind  into  families,  are  now  the  means  by  which 
they  are  associated.  Philosophical  chemistry  has  sub- 
jected the  elements  to  man’s  nse  ; and  all  tend  to 
the  final  accomplishment  of  the  great  objects  to  which 
every  thing,  from  the  beginning,  has  pointed  ; the 
multiplication  and  distribution  of  mankind,  and  the 
enlargement  of  the  sources  of  his  comfort  and  enjoy- 
ment— the  relief  from  too  incessant  toil,  and  the  con- 
sequent improvement  of  the  higher  faculties  of  his 
nature.  Instinct  has  directed  animals,  until  they  are 
spread  to  the  utmost  verge  of  their  destined  places  of 
abode.  Man  too  is  borne  onwards  ; and  although,  on 
consulting  Iris  reason,  much  is  dark  and  doubtful,  yet 
does  his  genius  operate  to  fulfil  the  same  design,  en- 
larging the  sphere  of  life  and  enjoyment. 

Whilst  we  have  before  us  the  course  of  human  ad- 
vancement, as  in  a map,  we  are  recalled  to  a narrower, 
and  yet  a more  important  consideration  ; for  what  to 
us  avail  all  these  proofs  of  divine  power — of  harmony 
in  nature — of  design — the  predestined  accommodation 
of  the  earth,  and  the  creation  of  man’s  frame  and  fa- 
culties, if  we  are  stopped  here  'I  If  we  perceive  no 
more  direct  relation  between  the  individual  and  the 
Creator  1 But  we  are  not  so  precluded  from  advance- 
ment : on  the  contrary,  reasons  accumulate  at  every 
step,  for  a higher  estimate  of  the  living  soul,  and  give 


208  ADDITIONAL  ILLUSTRATIONS,  &C. 

US  assurance  that  its  condition  is  the  final  object  and 
end  of  all  this  machinery,  and  of  these  successive 
revolutions. 

To  this,  must  be  referred  the  weakness  of  the  frame, 
and  its  liability  to  injury,  the  helplessness  of  infancy, 
the  infirmities  of  age,  the  pains,  diseases,  distresses, 
and  afflictions  of  life — for  by  such  means  is  man  to 
be  disciplined — his  faculties  and  virtues  unfolded,  and 
his  affections  drawn  to  a spiritual  Protector. 


THE 


CLASSIFICATION  OF  ANIMALS, 

IN  EXPLANATION  OF  THE  TERMS  INCIDENTALLY  USED  IN  THE 
VOLU3IE. 


The  Animal  Kingdom  is  arranged  in  four  Divisions  : 

Division  I.  Vertebral  Animals  ; so  called  from  their  possessing  a ver- 
tebral column  or  spine. 

Division  II.  Molluscous  Animals  : such  as  shell-fish,  which  are  of  a 
soft  structure,  and  without  a skeleton.  Etym.  mollis,  soft. 

Division  III.  Articulated  Animals  : like  the  worm  or  insect : they  are 
without  a skeleton,  but  their  skins  or  coverings  are  divided  and  jointed. 
Etym.  Articulus,  dim.  a joint. 

Division  IV.  Zoophytes : animals  believed  to  be  composed  very  nearly 
of  a homogeneous  pulp,  which  is  moveable  and  sensible,  and  resembles  the 
form  of  a plant.  Etym,  ^aov,  zoon,  a living  creature ; ipvTov,  phyton 
a plant. 


DIVISION  I. 

The  division  of  vertebral  animals  is  composed  of  four  Classes  : viz.,  1. 
Mammalia,  animals  which  suckle  their  young.  Etym.  mamma,  a teat. 
2.  Aves.  Etym.  avis,  a bird.  3.  Reptilia,  animals  that  crawl.  Etym.fcont 
a part  of  the  word  repo,  to  creep.  4.  Pisces.  Etym,  piscis,  a fish. 

The  first  Class  Mammalia,  is  divided  into  Orders,  w'hich  are  subdivided 
into  Genera,  and  these  are  further  divided  info  Species. 

Wc  present  the  principal  Orders  with  familiar  e.vamples. 

Bimana,  man.  Etym.  bis,  double  ; manus,  hand. 

18* 


210 


appendix. 


Q.uadrumana.  Etym.  quatuor,  four;  manus,  hand.  Monkeys,  ma- 
kis  or  lemurs  {Etym.  lemures,  ghosts.)  The  loris  tardigradus  (tar- 
dus, slow  ; gradior,  to  walk)  is  a species  of  lemur. 

Cheiroptera.  Etym.  xcip,  cheir,  the  hand  ; Trrcpov,  pteron,  a wing. 
The  Bats. 

Insectivora.  Etym.  insecta,  insects ; voro,  to  eat.  Hedge-hog  ; shrew  ; 
mole. 

Plantigrade.  Etym.  planta,  the  sole  of  the  foot  ; gradior,  to  walk. 
Bear  ; racoon. 

Digitigrade.  Etym.  digitus,  the  toe,  or  finger ; gradior,  to  walk.  Lion  ; 
wolf ; dog  ; weasel. 

Amphibia.  Etym.  apit,  ampAt,  both  ; ;3ios,  iios,  Hfe.  Walrus;  seal. 

Marsupialia.  Etym.  marsupium,  a pouch.  Kangaroo  ; opossum. 

Rodentia.  Etym.  rodo,  to  gnaw.  Squirrel  ; beaver  ; rat ; hare. 

Edentata.  Etym.  edentulus,  toothless  : animals  without  the  front 
teeth.  Ai;  unau  ; armadillo;  ant-eater;  tamandua;  megatherium 
(lieya,  mega,  great ; Sepiov,  therion,  a wild  beast) ; megalonyx  (/icyasi 
megas,  great ; onyx,  a claw)  ; ornithorhynchus  (opvidos  ; orni- 
tkos,  of  a bird  ; jmvxoSj  rhynchos,  a beak.) 

Pachydermata.  Etym.  naxvs,  pachys,  thick ; Seppa,  derma,  skin. 
Rhinoceros,  elephant;  mammoth:  mastodon  {pacrros,  mastos,  a 
nipple  ; oSinv,  odon,  a tooth)  ; tapir  ; horse  ; couagga. 

Ruminantia.  Etym.  ruminatio,  chewing  the  cud.  Camel;  giraffe; 
deer  ; goat ; cow  ; sheep. 

Cetacea.  Etym.  cetus,  a whale.  Dolphin ; whale ; dugong. 


Second  Class.  Aues,  or  Birds. 

Accipitres.  Etym.  accipiter,  a hawk.  Vulture;  eagle;  owl. 
Passeres.  passer, a sparrow.  Lark;  thrush;  swallow;  crow; 

wren. 

Scansores.  Etym.  scando,  to  climb.  Parrot;  wood-pecker;  toucan. 
Gallinae.  Etym.  gallina,  a hen.  Peacock  ; pheasant ; pigeon. 
Grallae.  Etym.  grallae,  stilts.  Ostrich  ; stork ; ibis  ; flamingo. 
Palmipedes.  Etym.  palma,  the  palm  of  the  hand  ; pes,  foot.  Swan  ; 
pelican  ; gull. 


Third  Class.  Reptiles. 

Chelonia.  Elpm.  chelys,^tortoisc.  Tortoise  ; turtle. 

Sauria.  Etym.  oavpa,  saura,  a lizard.  Crocodile  ; alligator , chame- 
leon ; dragon ; pterdoctyle  {nrepov,  pteron,  a wing  i iaKTv\os,  dacty- 


APPENDIX. 


211 


lus,  a finger) ; ichthyosaurus  (tx9vi,  ichthys,  a fish  ; aavfta,  savra,  a 
lizard)  ; plesiosaurus  (Tr^caiov,  plesion,  near  to;  craupa,  saura,  a rep» 
tile) ; megalasaurus  (ycyaXri^  megale,  great ; navga,  saura,  a reptile)  ; 
iguanadon. 

Ophidia.  Etym.  o(pts,  aphis,  a serpent.  Boa ; viper. 

Batrachia.  Etym.  0arpaxo{,  batrachos,  a frog.  Frog ; salamander  *, 
proteus. 

FounTH  Class.  Fishes. 

Chondropterygii.  Etym.  xovSfios,  chondros,  gristle ; irrrpvf,  pieryx,  the 
ray  of  a fin.  Ray  ; sturgeon  ; shark  ; lamprey ; ammocete  {appos, 
ammos,  sand  ; KtjTos,  cetos,  a fish.) 

Plectognathi.  Etym.  irXr™,  pleco,  to  join ; yt/aSo;,  gnathos,  the  jaw. 
Sun-fish  ; trunk-fish. 

Lophobranchi.  Etym.  \oipot,  lophos,  a loop ; /3payxia,  branchia,  the 
gills.  Pipe-fish  ; pegasus. 

Melacopterygii.  Etym.  paXaKos,  malahos,  soft ; xrepv^,  pteryx,  the  ray 
of  a fin.  Salmon ; trout ; cod  ; herring ; remora. 

Acanthopterygii.  Etym.  aKavBa,  acantha,  a thorn  ; Trrepv^,  pteryx,  the 
ray  of  a fin.  Perch  ; sword-fish  ; mackarel  ; lophius  piscatorrus 
{hoipia,  lophia,  a pennant ; piscator,  a fisher)  ; chsetodon  rostratus 
ixuire,  chcBte,  hair ; oiu>v,  odon,  a tooth  ; rostratus,  beaked)  ; zeus  ci- 
liaris  (ciliuin,  an  eye-lash.) 


DIVISION  II, 

MOLLUSCOUS  ANIMALS. 

1st  Class.  Cephalopoda.  Etym.  /ce^iaXt,  ccpAaZc,  the  head  ; noba,poda 
the  feet.  Animals  which  have  their  organs  of  motion  arranged  round  their 
bead. 

This  Class  includes  Sepia,  or  Cuttle-fish.  Argonauts  (Apya,  the  ship 
Argo,  vavrris,  nautes,  a sailor).  Nautilus,  (vavrat,  uautes,  a sailor.) 
Ammonite,  an  extinct  Cephalopode  which  inhabited  a shell  resembling 
that  of  the  Nautilus ; coiled  like  the  horns  of  a ram  or  of  the  statues 
of  Jupiter  Ammon  ; whence  the  name.  Belemnites  : also  extinct : 
the  shell  is  long,  straight,  and  conical  {PeXepvov,  belemnon,  a dart). 
Nummulites : likewise  extinct.  Whole  chains  of  rocks  are  formed 
of  its  shells.  The  pyramids  of  Egypt  are  built  of  these  rocks, 
(nummus,  a coin). 

2nd  Class.  Pteropoda.  Etym.  nrtpov,  pteron,  a wing  ; iroJo,  poda, 
feet ; having  fins  or  processes  resembling  wings  on  each  side  of  the  mouth. 


212 


APPENDIX. 


The  Clio  Borealis,  which  abounds  in  the  North  Seas,  and  is  the  prin- 
cipal food  of  the  whale. 

3rd  Class.  Gasteropoda.  Etym.  yacrrip,  gaster,  the  stomach  ; rola, 
poda,  the  feet.  Animals  which  move  by  means  of  a fleshy  apparatus  placed 
under  the  belly. 

The  snail  ; slug ; hmpet. 

4th  Class.  Acephala.  Etym.  a,  Q,  without ; xe^aXi?,  cephale,  the  head. 
Molluscous  animals  without  a head. 

The  oyster ; muscle. 

5th  Class.  Brachiopoda.  Etym.  Ppax‘ov,  brachion,  the  arm ; m(a 
poda,  the  feet.  Animals  which  move  by  means  of  processes  like  arms. 

Lingula  ; terebratula. 

6th  Class.  Cirrhopoda.  Etym.  cirrus,  a lock  or  tuft  of  liair ; ffo^a, poda, 
the  feet. 

Balanus  ; barnacle  • anatifera,  (anas,  a duck,  fero,  to  bring  forth.) 


DIVISION  III. 

ARTICULATA. 

1st  Class.  Annelides,  or  Vermes.  Etym.  Annellus,  a little  ring  ; vermU, 
a worm. 

Leech ; sea-mouse  ; earth-worm  ; sand-worm ; tubicolae,  (tubus,  a 
tube,  colo,  to  inhabit)  ; worms  which  cover  themselves  by  means  of 
a slimy  secretion  that  ejtudes  from  their  surfaces,  with  a case  of  small 
shells  and  pebbles,  like  the  caddis-worm,  or  with  sand  and  mud. 

2nd  Class.  Crustacea.  Animals  which  have  a shelly  crust,  covering 
their  bodies. 

The  crabs;  shrimps;  lobsters. 

3rd  Class.  Arachnida.  jEtym.  apaxrjrSi  ®t'ac/i7ies,  a spider. 

Spiders  ; aranea  scenica,  or  saltica ; the  leaping  spider  ; the  scorpion 
spider  ; the  mite. 

4th  Class.  Insecta.  They  are  divided  into  insects  which  are  without 
wings  and  those  which  have  them ; and  these  are  further  subdivided  accord- 
ing to  the  peculiarities  of  the  wings. 

Aptera  (a,  a,  without  ; jrrrpov,  pter<m^  a wing.)  Centipede  (having  a 
hundred  feet) ; louse;  flea. 

Coleoptera  (koAeos,  eoleos,a  sheath  or  scabbard,  irrEpov,  a wing),  insects 
which  have  their  wings  protected  by  a cover,  as  the  beetle,  corn- 
weevil.  Orthoptera  {opdos,  orthos,  straight,  Trrepov),  as  the  locust, 
grass-hopper.  Eemiptera  {{jpnov,  hemisu,  half,  TVEpov),  insects  which 
have  one  half  of  their  wings  thick  and  coriaceous,  and  the  other 


APPENDIX. 


213 


membranous  ; such  as  a bug,  tick,  fire-fly.  Neuroptera  (vcijpov,  neu- 
ron, a nerve, TTTfpov), dragon-fly ; ant-lion;  ephemera.  Hymenoptera 
(vpcv,  hymen,  a membrane,  irrcpov),  the  bee;  wasp;  ant.  Lepi- 
do^tera  (Actij,  lepis,  a scale,  iTTcpov),  moth  ; butter-fly.  Rhipiptera 
(limis, Tipis,  a fan,  -uTepov),  xenos  ; stylops.  Diptera  {St;,dis  double, 
TTspov),  house-fly ; gnat. 


DIVISION  rv. 

ZOOPHVTES. 

Echinodermata  (Etym.  exivos,  echinos,  a hedgehog  ; ieppa,  derma,  the 
skin),  the  star-fisn ; sea  urchin.  Entoza  (ev-ros,  entos,  within ; ^aS  zao, 
tolive),tsniahydatia.  ^calephre  (aKa^y<pn,  acnl^he,  a nettle),  medu- 
sa ; polypi  (containing  much  sap  ; sea-anemone  ; hydra  ; tubipora  (in- 
habiting tubes)  ; sertularia ; cellularia;  flustra ; coralline;  sponge. 
Infusoria  (found  in  infusions  or  stagnant  water),  monas  ; vibrio  ; 
proteus. 


THE  END. 


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New  WorkSy  pakllsked  by  Carey^  Iiea,  & B]aiickard< 


BRIDGEWATER  TREATISES. 


This  series  of  Treatises  is  published  under  the  following  circum- 
stances:— 

The  Right  Honorable  and  Rev.  Francis  Henry,  Earl  of  Bridge- 
water,  died  in  the  month  of  February,  1825 ; he  directed  certain  trus- 
tees therein  named,  to  invest  in  the  public  funds,  the  sum  of  eight 
thousand  pounds  sterling;  this  sum,  with  the  accruing  dividends 
thereon,  to  be  held  at  the  disposal  of  the  President,  for  the  time  being, 
of  the  Royal  Society  of  London,  to  be  paid  to  the  person  or  persons 
nominated  by  him.  The  Testator  farther  directed,  that  the  person  or 
persons  selected  by  the  said  President,  should  be  appointed  to  write, 
print  and  publish  one  thousand  copies  of  a work,  on  the  Power,  Wis- 
dom, and  Goodness  of  God,  as  manifested  in  the  Creation ; illustra- 
ting such  work,  by  all  reasonable  arguments,  as,  for  instance,  the  va- 
riety and  formation  of  God’s  creatures  in  the  Animal,  Vegetable,  and 
Mineral  Kingdoms ; the  effect  of  digestion,  and,  thereby,  of  conver- 
sion; the  construction  of  the  hand  of  man,  and  an  infinite  variety  of 
other  arguments  ; as  also  by  discoveries,  ancient  and  modern,  in  arts, 
sciences,  and  the  whole  extent  of  literature. 

He  desired,  moreover,  that  the  profits  arising  from  the  sale  of  the 
works  so  published,  should  be  paid  to  tire  authors  of  the  works. 

The  late  President  of  tlie  Royal  Society,  Davies  Gilbert,  Esq.  re- 
quested the  assistance  of  his  Grace,  the  Archbishop  of  Canterbury, 
and  of  the  Bishop  of  London,  in  determining  upon  the  best  mode  of  j 
carrying  into  effect,  the  intentions  of  the  Testator.  Acting  with  their  j 
advice,  and  with  the  concurrence  of  a nobleman  immediately  connect-  ; 
ed  with  the  deceased,  Mr.  Davies  Gilbert  a])pointed  the  following  eight  j 
gentlemen  to  write  separate  Treatises  in  the  different  branches  of  the  1 
subjects  here  stated: — 

I.  The  Adaptation  of  External  Nature  to  the  Moral  and  Intellec- 
tual Constitution  of  Man,  by  the  Rev.  Thomas  Chalmers,  D.  D.,  Pro- 
fessor of  Divinity  in  the  University  of  Edinburgh. 

II.  The  adaptation  of  External  Nature  to  the  Physical  Condition 
of  Man,  by  John  Kidd,  M.  D.,  F.  R.  S.,  Regius  Professor  of  Medicine 
in  the  University  of  Oxford. 

HI.  Astronomy  and  General  Physics,  considered  with  reference  to 
Natural  Theology,  by  the  Rev.  Win.  Whewell,  M.  .A.,  F.  R.  S.,  Fel- 
low of  Trinity  College,  Cambridge. 

IV.  The  hand : its  mechanism  and  vital  endowments  as  evincinir 
design,  by  Sir  Charles  Bell,  K.  H.,  F.  R.  S. 

V.  Animal  and  Vegetable  Physiology,  by  Peter  Mark  Roget,  M.  D., 
Fellow  of  and  Secretary  to  the  Royal  Society. 

VI.  Geology  and  Mineralogy,  by  the  Rev.  Wm.  Buckland,  D.  D., 
F.  R.  S.,  Canon  of  Christ  Church,  and  Professor  of  Geology  in  the 
University  of  Oxford. 

VII.  The  History,  Habits,  and  Instincts  of  Animals,  by  the  Rev. 
Wm.  Kirby,  M.A.,  F.R.S. 


New  WorkS)  puklished  hy  Careyy  iLea^  & Blanchard* 


BRIDGEWATER  TREATISES. 


VIII.  Chemistry,  Meteorology,  and  the  Function  of  Digestion,  by 
Wm.  Prout,  M.  D.,  F.  R.  S. 

THE  FOLLOWING  ARE  PUBLISHED. 

ASTRONOMY  AND  GENERAL  PHYSICS,  considered  with 
reference  to  Natural  Theology.  By  the  Rev.  William  Whe- 
WELL,  M.  A.,  Fellow  and  Tutor  of  Trinity  College,  Cam- 
bridge ; being  Part  III.  of  the  Bridgewater  Treatises  on  the 
Power,  Wisdom,  and  Goodness  of  God,  as  manifested  in  the 
Creation.  In  one  vol.  12mo. 

“ It  is  a work  of  profound  invesliiration,  deep  research,  distinguished  alike 
for  the  calm  Christian  spirit  which  breathes  throughout,  and  the  sound,  irre- 
sistible argumentation  which  is  stamped  on  every  page.” — Dai/y  Jntelli- 
gencer. 

“ Let  works  like  that  before  us  be  widely  disseminated,  and  the  bold,  active, 
and  ingenious  enemies  of  religion  be  met  by  those,  equally  sagacious,  alert  and 
resolute,  and  the  most  timid  of  the  many  who  depend  upon  the  few,  need  not 
fear  the  host  that  comes  with  subtle  steps  to  ‘steal  their  faith  away.’  ” — vV.  Y. 
Jimerican. 

That  the  devoted  spirit  of  the  work  is  most  exemplary,  that  we  have  here 
and  there  found,  or  fancied,  room  for  cavil,  only  pc-radveniure  because  we  have 
been  unable  to  follow  the  author  tlirough  the  prodigious  range  of  his  philo- 
sopliical  survey — and  in  a word,  that  the  work  before  us  would  have  made  the 
reputaiion  of  any  other  man,  and  may  well  maintain  even  that  of  Professor  . 
VVhewell.” — ^letropolitari . \ 

“ lie  has  succeeded  admirably  in  laying  a broad  foundation,  in  the  light  of  I 
nature,  for  the  reception  of  the  more  glorious  truths  of  revelation  ; and  has  \ 
produced  a work  well  calculated  to  dissipate  the  delusions  of  scepticism  and  \ 
infidelity,  and  to  confirm  the  believer  in  liis  faith.  ' — Charleston  Courier.  \ 

“ The  known  talents,  and  high  reputation  of  the  author,  gave  an  earnest  of 
excellence,  and  nobly  lias  Mr.  Whewell  redeemed  the  pledge.— In  conclusion, 
we  have  no  hesitation  in  saying,  that  the  present  is  one  of  the  best  works  of 
its  kind,  and  admirably  adapted  to  the  end  proposed;  as  such,  we  cordially 
recommend  it  to  our  readers.” — London  Lit.  Gazette. 

“ It  is  a work  of  high  cliaracter.” — Boston  Recorder. 

A TREATISE  ON  THE  ADAPTATION  OF  EXTERNAL 
NATURE  TO  THE  PHYSICAL  CONDITION  OF  MAN,  ^ 
principally  with  reference  to  the  supply  of  his  wants,  and  the  ^ 
exercise  of  his  intellectual  faculties.  By  Joh.n  Kidd,  M.  D.,  : 
F.  R.  S.,  Regius  Professor  of  Medicine  in  the  University  of  ■ 
Oxford  ; being  Part  II.  of  the  Bridgewater  Treatises  on  the  1 
Power,  Wisdom,  and  Goodness  of  God,  as  manifested  in  the  | 
Creation.  In  one  vol.  12mo. 

“It  is  ably  written,  and  replete  both  with  interest  and  instruction.  The 
diffusion  of  such  works  cannot  fail  to  be  attended  with  the  happiest  effects  in 
jiistifyini  ‘the  ways  of  God  to  man,'  and  illustrating  the  wisdom  and  good- 
ness of  the  Creator  by  arguments  w liich  appeal  irresistably  both  to  the  reason 
and  the  feelings.  Few  can  understand  abstract  reasoning,  and  still  fewer  rel- 
ish it,  or  will  listen  to  it : but  in  this  work  the  purest  morality  and  the  kindli- 
est feelings  are  inculcated  through  the  medium  of  agreeable  and  useful  infor- 
mation.”—Raff.  Oai. 

••  It  should  he  in  the  hands  of  every  individual  who  feels  disposed  to  ‘ vindi- 
cate the  ways  of  God  to  man.’  ” — A".  Y.  Com.  Adv, 


New  WorkS)  puklislied  by  Carey^  lica^  Blanchard* 


BRIDGEWATER  TREATISES. 


“ No  one  will  read  this  book  without  profit;  it  is  certainly  one  of  the  most 
interesting  volumes  we  have  ever  read,” — Philadelphia  Gazette. 

“Dr.  Kidd  has  fulfilled  his  task,  and  may  claim  the  gratitude  of  those  who 
delight  to  contemplate  the  wisdom  of  Providence  in  the  works  of  nature,  and 
to  discover  the  adaptation  of  the  vegetable  to  the  animal  world,  and  the  sub- 
serviency of  the  whole  to  the  high  destinies  of  man.” — U.  S.  Gazette. 

“ The  subject  has  been  ably  treated  by  a learned  professor,  and  though  it  is 
not  the  most  captivating  topic  in  the  world,  has  certainly  served  to  display  the 
ability  of  a sound  thinker,  who  might  rise,  on  other  themes,  to  eloquence.” — 
Sat.  Evening  Post. 

“ We  congratulate  Professor  Kidd  on  the  production  of  his  work,  and  repeat 
the  commendation,  to  which,  as  a popular  treatise,  it  is  indisputably  entitled.” 
— Christian  Remembrancer. 

ON  THE  ADAPTATION  OF  EXTERNAL  NATURE  TO 
THE  MORAL  AND  INTELLECTUAL  CONSTITU- 
TION OF  MAN.  By  the  Rev.  Thomas  Chalmers,  D.  D.  ; 
being  Part  I.  of  the  Bridgewater  Treatises  on  the  Power, 
Wisdom,  and  Goodness  of  God,  as  manifested  in  the  Crea- 
tion. In  one  vol.  12mo. 

“ The  volumes  before  us  are  every  way  worthy  of  their  subject.  It  would 
seem  almost  supereiogetary  to  pass  any  judgment  on  the  style  of  a writer  so 
celebrated  as  Dr.  Chalmers.  He  is  well  known  as  a logician  not  to  be  baffled 
by  any  difflculties ; as  one  who  boldly  grapples  with  Ins  ilieine,  and  brings  every 
energy  of  his  clear  and  nervous  intellect  into  the  field.  No  sophistry  escapes 
his  eagle  visions — no  argument  that  could  either  enforce  or  illustrate  his  sub- 
ject is  left  untouched.  Our  literature  owes  a deep  debt  of  gratitude  to  the 
author  of  these  admirable  volumes.” — Lit.  Gazette. 

THE  HAND:  ITS  MECHANISM  AND  VITAL  ENDOW- 
MENTS, AS  EVINCING  DESIGN.  By  Sir  Charles 
Bell,  K.  G.  H.  ; being  Part  IV.  of  the  Bridgewater  Treatises 
on  the  Power,  Wisdom,  and  Goodness  of  God,  as  manifested 
in  the  Creation.  In  one  vol.  12mo. 


SOCIETY  AND  MANNERS 

IN  GREAT  BRITAIN  AND  IRELAND. 

By  the  Rev.  C.  S.  Stewart,  U.  S.  Navy,  Author  of  A Voyage 
to  the  South  Seas,  &c.  In  2 vols.  12mo.  In  the  press. 


MEN  AND  MANNERS  IN  AMERICA. 

By  Major  Hamilton,  Author  of  Cyril  Thornton,  Annals  of  Pen- 
insular Campaigns,  &c.  In  1 vol.  8vo. 


lyZBSlOIHE. 


! The  practice  of  PHYSIC.  By  W.  P.  Dewees,  M.  D.,  Ad- 
j junct  Professor  of  Midwifery,  in  the  University  of  Pennsylva- 
5 nia.  New  edition,  ^eatly  enlarged,  complete  in  one  vol.  8vo 

^ “ We  have  no  hesitation  in  recoininendirig  it  as  decidedly  one  of  the  best  sys- 
i terns  of  medicine  extant.  T!ic  tenor  of  tlie  work  in  general  reflects  the  highest  , 
? honor  on  Dr.  IJewecs’s  talents,  industry,  and  capacity  for  the  execution  of  the  I 
? nr.luous  task  which  l?e  had  underlakeii.  It  is  one  of  the  most  able  and  satisfac- 
I tory  works  wliicli  modern  times  liave  produced,  and  will  be  a sta.ndard  authori- 
ly.” — London  Med.  and  Surg.Joanial.Aug.  1830. 

! DEWEES  o.N-  THE  DISEASES  of  CHILDREN.  .5th  ed.  In  8vo. 

The  objects  of  this  work  are,  1st,  to  teach  those  who  have  the  charge  of 
children,  either  as  parent  or  guardian,  the  most  approved  methods  of  se- 
curing and  improving  their  physical  powers.  This  is  attempted  by  pointing 
out  the  duties  which  the  parent  or  the  guardian  owes  for  this  purpose,  to 
this  interesting,  but  helpless  class  of  beings,  and  the  manner  by  which  their 
I duties  shall  be  fulfilled.  And  2d,  to  render  available  a long  experience  to 
I these  objects  of  our  alfection  when  they  become  diseased.  In  attempting 
I this,  the  author  has  avoided  as  much  as  po.s.sible,  “ technicality and  has 
J given,  if  he  does  not  flatter  himself  too  much,  to  each  disease  of  which 
i he  treats,  its  appropriate  and  designating  characters,  with  a fidelity'  that 
I will  prevent  any  two  being  confounded  together,  with  the  best  mode  of 
5 treating  them,  that  either  his  own  experience  or  that  of  others  has  sug- 
5 gested. 

DEWEES  ON  THE  DISEASES  of  FEMALES.  4th  edition,  with 
Additions.  In  8vo. 

A COMPENDIOUS  SYSTEM  OF  MIDWIFERY;  chiefly 
designed  to  facilitate  the  Inquiries  of  those  who  may  be  pur- 
suing this  Branch  of  Study.  By  W.  P.  Dewees,  M.  D.  In 
j 8vo.  with  13  Plates.  Si.xlh  edition,  corrected  and  enlarged. 

The  elements  OF  THERAPEUTICS  and  MATERIA 
MEDICA.  By  N.  Chafji.vn,  M.  D.  2 vols.  8vo.  -5th  edition, 
corrected  and  revised. 

MANUAL  OF  PATHOLOGY : containing  the  Symptoms,  Di- 

iagnosis,  and  Morbid  Character  of  Diseases,  &c.  By  L.  IMar- 
tinet.  Translated,  with  Notes  and  Additions,  by  Jones  Quai.s. 
Second  American  Edition,  12mo. 

“We  strongly  recommend  M.  Martinet’s  Manual  to  the  profession,  and  es- 
pecially to  stinlcnts;  if  the  latter  wish  to  study  diseases  to  advantage,  they 
should  always  have  it  at  hand,  both  when  at  the  bedside  of  the  patient,  and 
w hen  making  post  mortem  examinations.” — jimerican  Journal  of  the  Medical 
Sciences,  A''o.  I. 

CLINICAL  ILLUSTRATIONS  OF  FEVER,  comprising  a 
Report  of  the  Cases  treated  at  the  London  Fever  Hospital  in 
1828-29,  by  Alexander  Tweedie,  M.  D.,  Member  of  the  Royal 
College  of  Physicians  of  London,  &c.  1 vol.  8vo. 

'•  In  short,  the  present  work,  concise,  unostentatious  as  it  is,  would  have  led 
US  to  think  that  Dr.  Tweedie  was  a man  of  clear  judgment,  unfettered  by  at- 
tachment to  any  fashionable  hypothesis,  that  he  was  an  energetic  but  judicious 
practitioner,  and  that,  if  he  did  not  dazzle  his  readers  with  the  brilliancy  of  the- 
oretical speculations  he  would  command  their  assent  to  the  solidity  of  his  didac- 
tic precepts.” — Med.  Chir.  Journal. 


The  anatomy,  PHYSIOLOGY,  and  DISEASES  of  the 
TEETH.  By  1‘homas  Bell,  F.  R.  S.,  F.  L.  S.  &c.  In  1 vol. 
8vo.  With  Plates. 

“ Mr  Bell  has  evidently  endeavored  to  construct  a work  of  reference  for  the 
practitioner,  and  a text-book  for  tlie  student,  containin''  a ‘ plain  and  practical 
ditrcst  of  the  information  at  present  possessed  on  the  subject,  and  results  of  the 
author’s  own  investigations  and  experience.’  "****•  We  must  now  take  leave 
of  Mr.  Bell,  whose  work  we  have  no  doubt  will  become  a class-book  on  the  im- 
portant subject  of  dental  surgery.''—Jf^ilico-CAirur^ical  Jicviei/7. 

“ We  have  no  hesitation  in  pronouncing  it  to  be  the  best  treatise  in  the  Eng- 
lish language.” — J\'‘orth  Anicricaa  Medical  and  Surgical  Journal,  Js'o.  19. 

AMERICAN  DISPENSATORY.  Ninth  Edition,  inaproved 
and  greatly  enlarged.  By  John  Redman  Coxe,  M.  D.  Professor 
of  Materia  Medica  and  Pharmacy  in  the  University  of  Penn- 
sylvania. In  1 vol.  8vo. 

This  new  etiilion  has  been  arranged  with  special  reference  to  the 
recent  Pharmacopceias,  published  in  Philadelphia  and  New-York. 

ELLIS’  MEDICAL  FORMULARY.  The  Medical  Formulary, 
being  a collection  of  prescriptions  derived  from  the  writings 
and  practice  of  many  of  the  most  eminent  Physicians  in  Ame- 
rica and  Europe.  By  Benjamin  Ellis,  M.  D.  3d.  edition. 
With  Additions. 

‘‘  We  would  especially  recommend  it  to  our  brethren  in  distant  parts  of  the 
country,  whose  insulated  situations  may  prevent  them  from  having  access  to  the 
many  authorities  which  have  been  consulted  in  arranging  the  materials  for  this  I 
work.” — Phil.  Med.  and  Phys.  Journal.  § 

MANUAL  OF  MATERIA  MEDICA  .\nd  PHARMACY.  By  | 
H.  M.  Edw.ards,  M.  D.  and  P.  Vavasseur,  M.  D.  comprising  | 
a concise  Description  of  the  Articles  used  in  Medicine ; their  | 
Physical  and  Chemical  Properties ; the  Botanical  Characters  of  I 
the  Medicinal  Plants;  the  Formulae  for  the  Principal  Officinal  I 
Preparations  of  the  American,  Parisian,  Dublin,  &c.  Piiarrna- 1 
copoeias ; with  Observations  on  the  proper  Mode  of  combining  | 
and  administering  Remedies.  Translated  from  the  French,  I 
with  numerous  Additions  and  Corrections,  and  adapted  to  the  | 
Practice  of  Medicine  and  to  the  Art  of  Pharmacy  in  tlie  United  i 
States.  By  Josevh  Togno,  M.  D.  Member  of  the  Philadelphia  f 
Medical  Society,  and  E.  Durand,  Member  of  the  Philadelphia  I 
College  of  Pliarmacy.  | 

It  contains  all  the  pharmaceutical  information  that  the  physician  can  desire,  | 
and  in  addition,  a larger  mass  of  information,  in  relation  to  the  properties,  &c.'  | 
of  the  different  articles  and  preparations  employed  in  medicine,  than  any  of  the  R 
dispensatories,  and  we  think  will  entirely  supersede  all  these  publications  in  the  5 
library  of  the  physician." — Am.  Journ.  of  the  Medical  Sciences.  | 

MEMOIR  ON  the  TREATMENT  of  VENEREAL  DISEASES  I 
WITHOUT  IMERCURY,  employed  at  the  Military  Hospital  of  ! 
the  Val-de-Grace.  Translated  from  the  French  of  H.  M.  J. 
Desruelles,  M.  D.  &c.  To  which  are  added,  Observations  by 
G.  J.  Guthrie,  Esq.  and  various  documents,  showing  the  results 
of  this  Mode  of  Treatment,  in  Great  Britain,  France,  Ger- 
many, and  Ameiica.  1 vol.  8vo. 


PHYSIOLOGIC^AX.  ZVZZSDZCmS. 


HISTORY  OF  CHRONIC  PHLEGMAvSLH,  OR  INFLAM- 
MATIONS, founded  on  Clinical  Experience  and  Pathological 
Anatomy,  exhibiting  a View  of  the  different  Varieties  and 
Complications  of  these  Diseases,  with  their  various  Methods 
of  Treatment.  By  F.  J.  V.  BaoussAis,  M.  D.  Translated  from 
the  French  of  the  fourth  edition,  by  Isa.ac  Hays,  M.  D.  and 
R.  Eglesfeld  Griffith,  M.  D.  Members  of  the  American 
Philosophical  Society,  of  the  Academy  of  Natural  Science, 
Honorary  Members  of  the  Philadelphia  Medical  Society,  &.c. 
&c.  In  2 vols.  8vo. 

EXAMINATION  OF  MEDICAL  DOCTRINES  AND  SYS- 
TEMS OF  NOSOLOGY,  preceded  by  Projwsitions  contain- 
ing the  Substance  of  Physiological  Medicine,  hy  J.  F.  V 
Broussais,  Officer  of  the  Roj'al  Order  of  the  Legion  of  Hon- 
or ; Chief  Physician  and  First  Professor  in  the  Military  Hos- 
pital for  Instruction  at  Paris,  &c.  Third  edition.  Translated 
from  the  French,  by  Isa.ac  Hays,  M.  D.  and  R.  E.  Grif- 
fith, M.  D.  In  2 vols.  8vo.  In  the  press. 

A TREATISE  ON  PHYSIOLOGY,  Applied  to  P.athology. 
By  F.  J.  V.  Broussais,  M.  D.  Translated  from  the  French, 
by  Drs.  Bell  and  La  Roche.  8vo.  Third  American  edition, 
with  additions. 

"We  cannot  too  strongly  rocommend  tlie  present  work  to  the  attention  of 
our  readers,  ami  indeed  of  alJ  those  who  wish  to  study  physiology  as  it  ought 
to  be  studied,  in  its  application  to  tiie  science  of  disease."  " We  may  safdy 
say  that  he  has  accomplished  his  task  in  a most  masterly  manner,  and  thus 
established  his  reputation  as  a most  excellent  physiologist  and  profound  pathol- 
ogist."— JioHh  JJmcrican  J\Icd.  and  Sfirg.  Journ.  Jan.  1827. 

THE  PRINCIPLES  AND  PRACTICE  OF  MEDICINE.  By 
Sajiuel  Jackson,  51.  D.  Adjunct  Professor  of  Medicine  in  tlie 
University  of  Pennsylvania.  8vo. 

THE  PRACTICE  OF  MEDICINE,  upon  the  Principles  of 
the  Physiological  Doctrine.  By  J.  G.  Coster,  M.  D.  Trans- 
lated from  the  French. 

An  EPITOME  of  the  PHYSIOLOGY,  GENERAL  ANA- 
TOMY, and  pathology  of  BICHAT.  By  Thomas 
Henderson,  M.  D.  Professor  of  the  Theory  and  Practice  of 
iledicine  in  Columbia  College,  Washington  City.  8vo. 

" The  Epitome  of  Dr.  Henderson  ought  and  must  find  a place  in  the  library 
of  every  physician  desirous  of  useful  knowledge  for  himself,  or  of  being  instru- 
mental in  imparting  it  to  others,  whose  studies  he  is  expected  ic  superintend." 
— Jf.  Med.  and  Surg.  Jonrn.  JW.  15. 

A TREATISE  on  FEVER,  considered  in  the  spirit  of  the  new 
medical  Doctrine.  By  J.  B.  Boisskau.  Translated  from  the 
French. 


MEDICINE,  &c. 


CHOLERA,  as  it  recently  appeared  in  the  towns  of  Newcastle 
and  Gateshead,  including  cases  illustrative  of  its  Physiology  and 
Pathology,  with  a view  to  the  establishment  of  sound  principles 
of  Practice.  By  T.  M.  Greenhow,  of  New'castle-upon-Tyne, 
Member  of  the  Royal  College  of  Surgeons  in  London,  &c.  &.c. 
&c.  In  1 vol.  8vo. 

MANUAL  OF  GENERAL,  DESCRIPTIVE,  and  PATHO- 
LOGICAL ANATOMY.  By  J.  F.  Meckel,  Professor  of 
Anatomy  at  Halle,  &c.  Sic.  Translated  from  the  French,  witli 
Notes,  by  A.  Sidney  Doane,  A.  M.  RI.  D.  3 vols.  8vo. 

“ It  is  among  the  most  classical,  learned,  and  authoritative  treatises  on  Anat- 
omy.” — American  Journal  of  Med.  Science. 

A PRACTICAL  GUIDE  to  OPERATIONS  on  the  TEETH. 
By  James  Snell,  Dentist.  In  1 vol.  8vo.  with  Plates. 

“Those  of  our  readers  who  practise  in  the  department  of  Surgery,  on  wliich 
Mr.  Snell’s  essay  treats,  will  find  some  useful  instructions  on  the  mode  of  extract- 
ing teeth.” — Med.  Gazette. 

“This  is  an  excellent  practical  work,  and  will  be  found  generally  useful.”— 
Athenaum. 

“This  is  the  best  practical  manual  for  the  dentist  we  have  seen  in  the  English 
language.” — Gaz.  of  Health. 

PRINCIPLES  OF  PHYSIOLOGICAL  MEDICINE,  including 
Physiology,  Pathology,  and  Therapeutics,  in  the  form  of  Pro- 
positions, and  commentaries  on  those  relating  to  Pathology,  by 
F.  J.  V.  Broussais,  &c.  ; translated  by  Isaac  Hays,  M.  D.  and 
R.  E.  Griffith,  M.  D.  In  8vo.  | 

“ The  present  v^'ork  will/orm  an  indispensable  addition  to  the  library  of  every 
physician.  It  is  a very  important  and  necessary  companion  to  the  Treatise  on 
Physiology  as  applied  to  Pathology,  by  the  same  author.” — American  Journal 
of  Mod.  Science. 

PRINCIPLES  OF  SURGERY.  By  John  Syme,  Professew  of 
Surgery  in  the  University  of  Edinburgh.  In  8vo. 

HUMAN  PHYSIOLOGY,  illustrated  by  numerous  EngTavings  ; 
by  Robley  Dunglison,  M.  D.,  Professor  of  Physiology,  Pathol- 
ogy, &c.  in  the  University  of  Virginia,  Member  of  the  American 
Philosophical  Society,  <Sic.  2 vols.  8vo. 

It  is  the  most  complete  and  satisfactory  system  of  Physiology  in  the  English 
language.  It  will  add  to  the  already  high  reputation  of  the  author.”— 

Journal  of  Med.  Science, 

A TREATISE  on  the  DISEASES  of  the  EYE.  By  William 
Lawrence,  M.  D.  I vol.  8vo.  In  the  press. 

“It  is  almost  unnecessary  to  say,  iliat  it  contains  marks  of  vast  erudition 
and  exact  judgment,  and  that  experience  has  dictated  the  principles  that  are 
comprised  in  them,  experience  drawn  from  a hospital  devoted  solely  to  the  treat- 
ment of  diseases  of  the  Eye.” — Billaud. 

A TREATISE  on  DISEASES  of  the  HEART  and  GREAT 
VESSELS.  By  J.  R.  Bertin.  Edited  by  G.  Bouillaud.  Trans- 
lated from  the  French.  8vo. 


MEBICIK’E  SURGERY, 


A TREATISE  on  P'EVER.  By  Southwood  Smith,  M.  D., 
Physician  to  the  London  Fever  Hospital. 

“ No  work  lias  been  more  laiule.l  by  rhe  Previews  than  the  'IVeatise  on  Fevers, 
by  Southwootl  Smith.  Dr.  Johnson,  the  nlilor  of  the  Modico-t’hirur^jical  Kc* 
view,  says,  ‘ It  i?  the  best  we  have  ever  perused  on  the  subject  of  fever,  nnd  in 
our  conscience,  vve  believe  it  the  be.«t  that  ever  flowed  from  the  pfui  of  physician 
in  any  age  or  in  any  country.’  ” — Jim.  Med.  Journ. 

An  essay  on  REMITTENT  and  INTERMITTENT  DIS- 
EASES, including  generically  Marsh  Fever  and  Neuralgia — 
comprising  under  the  former,  various  Anomalies,  Obscurities, 
and  Consequences,  and  under  a new  systematic  View  of  the 
latter,  treating  of  Tic  Douloureux,  Sciatica,  Headache,  Oph- 
thalmia, Toothache,  Palsy,  and  many  other  Modes  and  Conse- 
quences of  this  generic  Disease;  by  John  1\Iacci;ij/)cti,  ,M.  D., 
F.  R.  S.  &c.  &c. 

“ In  rendering  Dr.  Macculloch's  work  nwre  accessible  to  the  pr(»fession,  we ar.^ 
conscious  that  we  are  doing  the  state  some  service.” — Med.  Ckir.  heviae. 

‘ We  most  strongly  recommend  Dr.  Macculloch's  treatise  to  the  aitemion  of 
our  medical  brethren,  as  presenting  a most  valuable  mass  of  iiiformalioii,  on  a 
most  important  subject.’' — A*.  A.  Med.  and  Surg.  Journal. 

A PRACTICAL  SYNOPSIS  OF  CUTANEOUS  DISEASES, 
from  the  most  celebrated  Authors,  and  particularly  from  Docu- 
ments afforded  by  the  Clinical  Lectures  of  Dr.  Biett,  Physician 
to  the  Hospital  of  St.  Louis,  Paris.  By  A.  Cazenave,  M.  D 
and  H.  E.  Schedel,  M.  D. 

We  can  safely  recommend  this  work  to  the  attention  of  practitioners  as  con- 
taining much  practical  information,  not  only  on  the  treatment,  but  also  on  the 
causes  of  cutaneous  affections,  as  being  in  fact  the  best  treatise  on  diseases  »»f 
the  skin  that  has  ever  appeared.” — American  Journal  of  the  Medical  Sciences , A“e.  5. 

SURGICAL  MEMOIRS  OF  THE  RUSSIAN  CAMPAIGN. 

Translated  from  the  French  of  Baron  Larrey. 

LECTURES  ON  INFLAMMATION,  exhibiting  a view  of 
the  General  Doctrines,  Pathological  and  Practical,  of  ^ledica) 
Surgery.  By  John  Tho.mpson,  M.  D.,  F.  R.  S.  E.  Second 
American  edition. 

THE  INSTITUTES  AND  PRACTICE  OF  SURGERY: 
being  the  Outlines  of  a Course  of  Lectures.  By  W.  Gibson, 
]\I.  D.  Professor  of  Surgery  in  the  University  of  Pennsyh  ania. 
3d  edition,  revised,  corrected,  and  enlarged.  In  2 vols.  8vo. 
PRINCIPLES  OP  AHLITARY  SURGERY,  comprising  Ob- 
servations on  the  Arrangements,  Police,  and  Practice  of  Hos- 
pitals, and  on  the  History,  Treatment,  and  Anomalies  of  Va- 
riola and  Syphilis ; illustrated  with  cases  and  dissections.  By 
John  Hennen,  M.  D.,  F.  R.  S.  E.  Inspector  of  Military  Hos- 
pitals— first  American  from  tlie  third  London  edition,  with  the 
Life  of  the  Author,  by  his  son,  Dr.  John  Hennen. 

“The  value  of  Dr.  Hennen's  work  is  too  well  appreciated  to  need  any  praise 
of  ours.  We  were  only  required  then,  to  bring  the  third  edition  before  the 
notice  of  our  readers;  and  having  done  tins,  we  shall  merely  add,  that  tlie  vol- 
ume merits  a plane  in  every  library,  and  that  no  military  surgeon  ought  to  be 
without  it.” — Medical  Oaictte. 


ANATOMY 


DCRECTIONS  for  MAKING  ANATOMICAL  PREPARA- 
TIONS, formed  on  the  basis  of  Pole,  Marjolin  and  Breschet, 
and  including'  the  new  method  of  Mr.  Swan,  b}'  Usher  Parsons, 
M.  P.  Professor  of  Anatomy  and  Surgery.  Li  1 Vol.  8vo.  with 
plates 

A TREATISE  on  PATHOLOGICAL  ANATOJIY.  By  Wil- 
liam E.  Horner,  M.  D.  Adj.  Prof,  of  Anatomy  in  the  Univer- 
sity of  Pennsylvania. 

“ We  can  conscientiously  commend  it  to  the  menibcrs  of  the  profession,  as  a 
satisfactory,  interesting,  and  instructive  view  of  the  subjects  discussed,  and  as 
well  adapted  to  aid  them  in  forming  a correct  appreciation  of  the  diseased  con- 
ditions they  are  called  on  to  relieve.” — American  Journal  of  the  Medical  Science, 
JVo.  9. 

By  the  same  Author. 

I A TREATISE  on  SPECIAL  and  GENERAL  ANATOMY. 
Third  edition,  revised  and  corrected,  in  2 Vols.  8vo. 

LESSONS  IN  PRACTICAL  ANATOMY,  for  the  use  of  Dis- 
sectors. 2d  edition,  in  1 Vol.  8vo. 

SYSTEM  OF  ANATOMY,  for  the  use  of  Students  of  Medicine. 
By  Caspar  Wistar.  Fifth  edition,  revised  and  corrected,  by 
W.  E.  Horner,  Adjunct  Professor  of  Anatomy  in  tlie  Univer- 
sity of  Pennsylvania.  In  2 Vols.  8vo.  | 

ELEMENTS  of  GENERAL  ANATOMY,  or  a description  of  I 
the  Organs  comprising  the  Human  Body.  By  P.  A.  Beclard,  | 
Professor  of  Anatomy  to  the  Faculty  of  Medicine  at  Paris.  | 
Translated  by  J.  Togno.  | 

TREATISE  ON  SURGICAL  ANATOMY.  By  Abraham  Col-  | 
LES,  Professor  of  Anatomy  and  Surgery,  in  the  Royal  College  3 
of  Surgeons  in  Ireland,  &c.  Second  American  edition,  with  | 
notes  by  J.  P.  Hopkinson,  Demonstrator  of  Anatomy  in  the  | 
I University  of  Pennsylvania,  &c.  &c.  | 

A TREATISE  on  PATHOLOGICAL  ANATOMY.  By  E.  | 
Geddings,  M.  D.  Professor  of  Anatomy  in  the  Medical  Coilege  i 
of  South  Carolina.  In  2 vols.  8vo.  (In  the  press.)  | 

I ELEMENTS  OF  MYOLOGY.  By  E.  Geddings,  M.  D.  illus- 1 
trated  by  a series  of  beautiful  Engravings  of  the  Muscles  of  the  | 
Human  Bod}',  on  a plan  heretofore  unknown  in  this  country,  j 
In  the  press.  I 

This  work,  in  addition  to  an  ample  and  accurate  description  of  the  gene- 1 
ral  and  special  anatomy  of  the  muscular  system,  will  comprise  illustrations  p 
of  the  subject  from  comparative  anatomy  and  physiology,  with  an  account  i 
of  the  irregularities,  variations  and  anomalies,  observed  by  the  various  an- 1 
eient  and  modern  anatomists,  down  to  the  present  time.  | 


CHSIVSSSTRY. 


THE  CHEMISTRY  OP  THE  ARTS,  on  the  basis  of  Gray’s 
Operative  Chemist,  being  an  Exhibition  of  the  Arts  and 
Manufactures  dependent  on  Chemical  Principles,  with 
numerous  Engravings,  by  ARTHUR  h.  PORTER,  M.  D. 
I late  Professor  of  Chemistry,  &c*  in  the  University  of  Ver" 
mont>  In  8vo.  With  niimerous  Plates. 

The  popular  and  valuable  English  work  of  Mr.  Gray,  which  forms  the 
groundwork  of  the  present  volume,  was  published  in  London  in  1829,  and 
designed  to  e.xhibit  a systematic  and  practical  view  of  the  numerous  Arts  and 
Manufactures  which  involve  the  application  of  Chemical  Science.  The  au- 
thor himself,  a skilful,  manufacturing,  as  well  as  an  able,  scientific  chemist, 
enjoying  the  multiplied  advantages  Morded  by  the  metropolis  of  the  greatest 
manufacturing  nation  on  earth,  was  eminently  quahfied  for  so  arduous  an 
undertaking,  and  the  popularity  of  the  work  in  England,  as  well  as  its 
intrinsic  merits,  attest  the  fidelity  and  success  with  which  it  has  been  ex- 
ecuted. In  the  work  now  offered  to  the  American  public,  the  practical 
character  of  the  Operative  Chemist  has  been  preserved,  and  much  extend- 
ed by  the  addition  of  a great  variety  of  original  matter,  by  numerous  cor- 
rections of  the  original  text,  and  the  adaptation  of  the  xvhole  to  the  state 
and  wants  of  the  Arts  and  Manufactures  of  the  United  States.  Among  the 
most  considerable  additions  will  be  found  full  and  extended  treatises  on  the 
' Bleaching  of  Cotton  and  Linen,  on  the  various  branches  of  Calico  Printing, 
on  the  Manufacture  of  the  Chloride  of  Lime,  or  Bleaching  Powder,  and 
numerous  Staple  Articles  used  in  the  Arts  of  Dying,  Calico  Printing,  and 
various  other  processes  of  Manufacture,  such  as  the  Salts  of  Tin,  Lead, 

I Manganese,  and  Antimony ; the  most  recent  Improvements  on  the  Manu- 
focture  of  the  Jiluriatic,  Nitric,  and  Sulphuric  Acids,  the  Chromates  of 
Potash,  the  latest  infonnation  on  the  comparative  Value  of  Diflerent  \'a- 
rielies  of  Fuel,  on  the  Construction  of  Stoves,  Fire-Places,  and  Sieving 
Rooms,  on  the  ^'entilation  of  Apartments,  <fcc.  &c.  The  leading  object  has 
been  to  improve  and  extend  the  practical  character  of  the  Operative  Chem- 
ist, and  to  supply,  as  the  publishers  (latter  themselves,  a deficiency  which 
is  felt  bv  every  artist  and  manufacturer,  whose  processes  involve  the  prin- 
I ciples  of  chemical  science,  the  want  of  a Systematic  Work  which  should 
embody  the  most  recent  improvements  in  the  chemical  arts  and  manufac- 
tures, whether  derived  from  the  researches  of  scientific  men,  or  the  ex- 
periments and  observations  of  the  operative  manufacturer  and  artisans 
themselves. 


CIIEMICAIi  MAIVIPULATIOX.  Instrciction  to  Students  on 
i file  MetUods  of  performing  Experiments  of  Demonstra- 
I tion  or  Rescarcli,  with  accuracy  and  success.  By  MICHAEU 
i FARADAY,  F.  R.  S.  First  American,  from  the  second 
I Uoiidon.  edition,  with  Additions  by  J.  tv.  3IITCHEI/I.,  M.  D. 

; “ .\ftcr  a very  careful  perusal  of  tliis  work,  we  strenuously  recommend  it,  as 

c.mtaining  the  most  complete  and  excellent  instructions  for  conducting  chemical 
experiments.  There  are  few  persons,  however  great  their  experience,  who  may 
not  gain  information  in  many  important  particulars;  and  for  ourselves,  we  beg 
most  unequivocally  to  acknowledge  that  we  have  acquired  many  new  and  im- 
portant liints  on  subjects  of  even  every-day  occurrence." — Philosophicai  Mag. 

“ A work  hitherto  e.xceedingiy  wanted  in  the  laboratory,  equally  useful  to  the 
proficient  and  to  the  student,  and  eminently  creditable  to  the  industry  and  skill 
of  the  author,  and  to  the  school  whence  it  emanates.” — Journal  of  Science  and 
Arts. 


I 

(T  Bell 

1833 


